Icom IC7300 A to Z #41 Using an External Antenna Tuner

NOTICE: In July 2021 the channel name changed from HamCuredSmoke
To Ham Radio A2Z. All of the earlier videos (like this one) are still available.
This time we'll take a look at connecting an external antenna tuner to the IC-7300. We'll also look at how the IC-7300 recognizes an external tuner. Icom doesn't release much information about how the external tuner connector works on their radios. I have used both the LDG IT-100 and the MFJ-939 tuners with my radio. I am using use the MFJ for this demonstration.
A number of people have done some experimenting and come up with various interfaces to use the radio with generic external tuners. Here are a few links that I have found useful:
www.vk3erw.com/index.php/11-eq...
www.prnewell.com/kc2wi/Icom_tu...
owenduffy.net/module/TuneMate...
forums.qrz.com/index.php?thre...

[@phillips2976]

Thanks a million! This is valuable information simply because there is absolutely NO information in the manual about using the MFJ 939i with an ICOM 7300. The MFJ website is a disaster when it comes to finding a manual. Fortunately, a dear soul sent me the manual as an attachment to an email. But it wasn't at all useful for my radio. My frustration level is now back down to normal. Many thanks.

[@douggalt]

Tom. Thank you so much for creating this series of videos. I am in the process of watching everyone of your IC7300 videos. I learn best by watching videos or someone actually preforming the tasks to be learned.

[@Gator_Bait_Motorsports]

Thanks for the videos. They sure help getting me up and running on my new Icom 7300. I bought the LGD IT-100 tuner to use with a myantenna OCF dipole 4010-3K antenna. All your videos are very good. Thanks again! WA9H, 73's

[@StanCook]

Once again Tom, thank you very much for teaching me about my “new” 7300,

[@JesusIsLordofMybeing]

Thanks so much Tom for this valuable tutorial. Just purchased a preowned 7300 and I absolutely love this radio. 73s

[@kevincollins1773]

Thanks Tom, this series is just what I needed.

[@davlyn376]

I just bought a 7300 and your videos make understanding its complexities easier. Tnx. Dave W2CGG

[@jes4596]

My MFJ 939i tuner is awesome ! Its on my 756 pro now. Im ordering a new 7300 tomorrow and will be using the 939i on the 7300. Thanks for the great vids !!

[@gryphonz3]

Thank You for this video. It saved me hours of aggravation and saved my sanity. Neither the Z-100 manual or the 7300 manual explained the tuning operation like this. It worked perfectly for me after I watched this. 7-3

[@swflKVNC]

Thank you Tom. Somehow you seem to sense what my current interest is. I have an MFJ SWR/Power meter that is giving me very different readings from my 7300. turns out the MFJ is bad. So, I started learning about tuning and the SWR function....and there you are!

[@Zif-the-Old-Herring]

Thank you. I watch these videos in a random order as a topic interests me. I bought an IC7300 but can not use it yet, I'm working on my General now. Just learning some small, common thing let's us feel we have some control over this radio. When I bought my first computer, learning to move desktop icons around was a mighty chest thumping feeling. 73 K5PML

[@HamRadioA2Z]

Thanks for watching! I’m glad they’re helpful.

[@1crazynordlander]

Thanks! I have the LDG AT100PROII tuner for my IC-7300. It came with a power cable so I had to buy the ICOM cable. I bought the IT-100 for my IC-7100. It came with the proper cable for ICOM radios.

[@drewmazer1799]

Tom, thanks for preparing a video regarding external tuners for the IC7300. Just ordered the MFJ 939 for the Chameleon Tactical Dipole.

[@genekauffman8286]

Tom very timely for me as I work my way thru your videos. My 7300 internal tuner won’t tune all the bands on my new vertical. The antenna manufacturing recommended the LDG. I like the plug and play as I was concerned about the setup. Your video cleared up my worries. Thanks. 73 NP2BB

[@glennstevenson6242]

I learn something new from every video you make. Thank you!

[@HamRadioA2Z]

Glad to hear it! Thanks.

[@nelsonwalker7105]

thank you I have an IC-7300 and an IT-100 tuner but I didn't understand the manual completely. This video helped me a lot. THank you very much.

[@gregmihran8616]

Great video as always Tom, thanks very much! I have both the IC-7300 and the MFJ-939 auto tuner. While not all MFJ products are 'great', the 939 is fantastic! It's fast, accurate and easy to use. (Worked better for me than the LDG product.) I power it off with a simple click when I just want to use the 7300 internal tuner for 'easy' matches, and then power it back on for the tougher matches (e.g. 160M and 80M on my HWEF 4010 antenna). I touch the 939 'ALT' button for my second antenna because it stores a complete different set of matches for that one. I've also noticed that if you tune the antenna more than once, it usually fine tunes the match even better. I've consistently noticed this effect by using the 7300 SWR band graphing tool. 73s Greg KJ6ER Silicon Valley

[@Tommy_Boy.]

Great video Tom! Thanks for sharing the goods. I’m running the 7300 and considering the 939 tuner, so this was very helpful! Cheers! 📻⚡️ - Tom

[@hook2364]

This is great, I always come to your channel to get the info for my 7300. Thanks for all that you do. K4OOH - 73

[@phredyh]

Tom... this is the first video of yours that I watched and read all the comments. Very well done. I just got an IC7610 a couple of months ago. I really like it but there is so much to learn. The 7300 and the 7610 I believe have a lot in common so I will so I am defiantly subscribed to Ham Cured Smoke. Keep up the great work! de Fred KE0EF

[@HamRadioA2Z]

Thanks Fred. A friend has the 7610. Its a really nice rig.

[@malcolmcooper9641]

Tom I learn something about the 7300 each time I watch your videos. Thank you vk2ab

[@HamRadioA2Z]

Thanks for the kind words Malcolm.

[@larryhinsdale4283]

Tom, thanks for your videos. I have had my IC7300 going on 4 years, I still learn from the videos. I would like to see a video on the SWR measurement function the radio has. This feature has been very helpful for me and I think others would find it useful as well.

[@HamRadioA2Z]

Hi Larry. Yes, that is another one of the lesser used features that I just haven't done a video for, yet. One will be coming. Thanks. Tom

[@ky4tgtodd203]

I appreciate your videos very much! They are very helpful! Thanks!

[@petersdelucaaa2vg306]

Tom Thanks for the great video. I replaced the back external tuner connection with a RX 7300 SMA. I enjoy having the ability to Rx on a separate antenna from my transmit antenna. The external connector is tucked under the radio cover. I can still use it if I make another cutout on the back. I’m contemplating replacing my Carolina Windom with a ladder line dipole for 80-10 meters. When running power I have an old Alpha 91b with a manual palstar tuner. I think that some IC 7300 users are not aware of the Emergency Mode setting which will tune an SWR 10:1. The only downside is that you will max the power at 50 watts. Theoretically that should decrease my signal by less than one S unit. Not a big change. Tnx agn for an informative video. Peter/ AA2VG

[@alancarter5141]

thanks tom i have the 939 and it is a great external tuner :)

[@resiggy13]

Interesting that your demonstration seemed to prove the point that the antenna must be tuned in order to receive as well as broadcast. I recently watched another highly subscribed KZbin HAM channel that was doing a livestream with the IC-7300 and he couldn't understand why several bands were "strangely empty." When a viewer pointed out that he needed to retune when switching bands he really berated that viewer and repeatedly said that there is no need to tune when only receiving . I guess I now know which YT channel to put into the "blowhard" bucket and which one to put in the "great reference" bucket. :) thanks for this really great series! You just got another new sub.

[@HamRadioA2Z]

Hi. First, thank you for the kind words. I’m glad you’re finding the channel useful. It is true that tuning isn’t “necessary” during receive, in that it won’t hurt the radio. However, it definitely can make a big difference on receive especially if you’re using a compromise antenna that can only be matched to small portions of bandwidth at any one time. I know that I have mistakes in some of my videos as well. I will promise that I won’t berate anyone for pointing out something wrong. I’ll either acknowledge the error or, if I do believe I’m right, I’ll do my best to calmly explain why I think something is correct. Thanks for watching! 73, Tom

[@mikemcdonald5147]

just found your ham cured smoke channel and subscribed. I have the 7100 I see you've done two videos on so far. Looks like a great channel. Thanks for sharing your knowledge.

[@HamRadioA2Z]

Awesome, thank you! Welcome to the channel. I hope you find it helpful.

[@CrittendenIV]

Thank you for your video. I just learned something I didnt realize I needed to know! :) :)

[@roberthildebrand9937]

Nicely done

[@weslewis8748]

I use an MFJ929 auto tuner without a data connection wire to the IC 7300. Works fine... I just turn power down to 5 watts... And transmit a CW signal... For a few seconds... To allow the MFJ 929 to adjust itself. In case there is a ham out there that already has an auto tuner... without a data line... Don't despair... You'll find it works great this way. After tuning up of course, I then bring power up to the 100 watts output

[@Dennis-sb7gp]

Thank you Tom, I was wondering about this problem

[@brianve7jyd943]

Mornin - just recieved my new 7300 and ldg tuner - this came along at the rite time - thankyou Sir and 73 VE7JYD

[@nickallsworth5697]

Really helpful thank you.

[@keithmarshall8478]

Your videos are very helpful

[@rbrucepierce139]

Tom, I liked your video on using an MFJ tuner with the Icom 7300. One extra thing you might have included was the function buttons on the MFJ. I think you assumed that connecting the two simply brought "up" the MFJ and that may well be the case. But I'm left wondering what the buttons on the MFJ are for or what they then do. Thanks, R B Pierce

[@donalddavis581]

there is another option... the MFJ 914 auto tuner extender. Well worth a look! Keeps it as simple as possible.

[@BobLewen]

Tom, your series on the 7300 has been great. I have the mfj 939 as well. You don’t have to pull the cable if you want to use only the 7300 internal tuner. Just power off the 939. The 7300 internal tuner will then tune the antenna, bypassing the 939.

[@HamRadioA2Z]

Thanks Bob! I never tried that. Seems like that should have been a pretty obvious thing to try too. Great tip. 73, Tom, WA2IVD

[@Airsoftforall]

Fine video. Just mine I have to power both the 939i and 7300 individually. When I had my 7100 I could just power the radio on and the 939i would power on as well.

[@RedNeckSurgeyTech]

Very helpful! Thanks KF0ALT

[@W4BTK]

thank you sir!

[@finpainter1]

good info.

[@massoud999]

Tom I saw your videos only yesterday and I learned a lot. Thanks for sharing. 73 de 4Z5UY

[@druliefw]

I have found the MFJ more forgiving of impedance mismatch than the LDG. I do have both and the LDG MUST have a balanced load where I can run my random wire directly to the MFJ 939. I use both tuners with my MARS station because the internal tuners of both my radios cannot handle the out of band conditions. My other radio is an IC745Pro. I have a second MFJ939 that works better with the second antenna port of the 745 without the control cable where the LDG AT100P is useless on that port when using ALE. The LDG works fine with my fan dipole that is cut to the MARS frequencies. 73 WB2HVF

[@andreweastland9634]

I dont have the 939 but I do have the 993 tuner. On this one I just press the power button to turn it off and then the 7300 uses it's internal tuner. This is useful on 6m & 4m which the 993 can't tune so I use the 7300 tuner here instead.

[@jimyohe100]

Just like you said, Andrew, I turn the power off to my MFJ-929 and the internal tuner stops working. No need to disconnect a cable by hand.

[@albertomlzioli1158]

Thanks so much. My Icom 7100 will arive in 3 days.......... :)

[@richardollins6079]

Your tutorials are fantastic. Best I've seen. I have learned a lot. I have a question. What is the best way to use an external tuner that is NOT ICOM compatible? Something like the RT-100 which is used at the antenna feedpoint.

[@HamRadioA2Z]

Hi Richard. Thanks for the kind words. I sometimes use an SGC, non-Icom specific tuner. It is pretty easy. You have at least a few options. The simplest is to put the rig into RTTY mode on your desired frequency. Then set the RF Output power to a safe level, maybe around 10%-20%. Refer to your tuner manual to see if it recommends a safe power for tuning. Then just key your mic. The radio will put out an unmodulated carrier. This should start your auto-tuners tuning sequence. Another option is to make an external Tune switch. This is a simple circuit connected to the rigs tuner connector that will force a low power, CW carrier regardless of the rig's mode and power settings. There are a number of descriptions on the internet. One is here: www.prnewell.com/kc2wi/Icom_tune_control/index.htm 73, Tom

[@martindrury9740]

Great Video. Many Thanks. M7MGD (UK)

[@HamRadioA2Z]

Glad you enjoyed it

[@martindrury9740]

@@HamRadioA2Z Look forward to seeing more on the 7300.

[@si12volt1]

I was wondering if I put my MFJ 949E on bypass just use it as a switch between bypass COAX 1 and bypass COAX 2 and put the OUTPUT Cable TO THE MFJ-939 tuner to tune if it work ..just to be able to access both antennas like a switch.... or just get a switch a/b switch

[@fredshead3956]

Hi Tom, another good video, friend f mine has just bough LDV tuner and wasnt quite sure how to use it so i sent him this link..hope your well from Fred g4vvq Uk.

[@Klaatu-ij9uz]

QUESTION -- This is a question not related to this current episode. I like to exclusively wear headphones while transmitting voice SSB. While utilizing the 7300's transmit audio monitor feature, can I use this feature "continually" without causing difficulties to the radio? I'm fearing that the monitor feature is only meant for preliminary "testing" voice audio. Thank you.

[@HamRadioA2Z]

Hi Philip. There is absolutely no issue with leaving the monitor on all the time. It is fine for "testing" your audio continuously. One thing that it can help with is to alert you if you have a loose or intermittent connection in your microphone as this can easily happen as our equipment gets older. Thanks for watching. 73, Tom WA2IVD

[@onemorething100]

Not sure if you still monitor these videos but hope you can answer a question. I have the LDG tuner and the 7300. When I tune, should the RF power be turned down? If so is that to avoid interference or does it harm the radio to tune with full power. I move around on the bands a lot and sometimes I forget to turn the power down. I have the Tune on when PTT is active. Also, when tuning should it be in another mode other than SSB? I’ve seen it written that you should change to CW or FM. Thank You.

[@HamRadioA2Z]

If you press and hold the TUNE button to activate the tuner, it starts a tuning sequence. The radio automatically turns the power down to about 10 watts (regardless of power setting) and puts out a single, CW carrier until the tuner is done. If you have the automatic tune on PTT enabled, it will not begin tuning if you just press PTT in SSB mode without speaking into the mic. In SSB, the carrier is suppressed. So, there is no output power unless there is audio. It won’t be able to detect the SWR or start tuning until you speak (or play a steady tone). For that reason, I don’t enable the tune on PTT feature. If there is a high SWR, the tuner/radio won’t detect that until you start speaking. When you are speaking, the output power is jumping up and down with your voice. As the output power is jumping all over, so is the reflected power that the tuner uses to calculate SWR. So it is very difficult for it to do a good job tuning. I suggest leaving the PTT feature disabled and just press the TUNE button when you switch frequencies or bands. 73, Tom

[@Raven_of_Doom]

Hi Smoke, at 2:56, regarding the PTT Start---I do like that feature. So if I have the PTT Start enabled, when I change bands and transmit, the 939i will automatically tune? I won't have to press tune on the radio or 939i, correct? thanks!

[@HamRadioA2Z]

Yes. That's correct.

[@larryak0z672]

Will the external tuner be bypassed when it is shut off? What is the ALT button for? Thanks.

[@rbrucepierce139]

Tom, the MFJ 939 manual states that for the Icom radios supported, the JP2 Jumper in the tuner must be set to the "I" setting. I don't think you mention this on your KZbin: is this the case? I assume this involves removal of the case on the tuner; it seems to work with the 7300 without doing this... is it a necessary step?

[@shawnp6653]

Great series - will be spending a lot of time re-watching once I get my 7300 up and running. May I ask what you have the 7300 grounded to? I have read a BUNCH of back and forth on grounding to the point of confusion, so I just wanted to ask. Regardless, thanks for the time you have spent on this series.

[@HamRadioA2Z]

Hi Shawn. Ham discussions on grounding are a lot like discussions about religion and politics. People have very strong held beliefs and convictions. My ground is, honestly, not that great. I am in a rental house for the time being and don't have a great permanent setup. I do have a safety ground through my power outlet coupled with a ground rod driven just on the other side of the wall from my hamshack where I was able to sneak it into the house. A good place to start is a grounding FAQ page from the ARRL. You can find that here: www.arrl.org/grounding That at least explains the different types of grounds and gives some explanation of which ones you need and why. Thanks for watching. 73, Tom

[@shawnp6653]

@@HamRadioA2Z Thanks Tom. Had to laugh at your comment re: grounding discussions - I appreciate folks' passion on the topic, it does remind me of politics/religion/Chevy vs Ford/etc. Asked mainly to pick up another nugget of information :) Thanks for the link - will read & bookmark it. Love the channel - thanks for your time/effort to put out quality content. Be safe!

[@bluestarindustrialarts7712]

New Ham here. So I watched the vid on the internal tuner. Now I watched this. So does it go without saying that an external tuner is perhaps not 'required' equipment. But highly preferable? BTW I subbed and intend to watch every 7300 video you have. It is my radio of choice as I venture into this new hobby. Hits the sweet spot of quality, features, price. No call sign yet, I passed Tech and General just 2 days ago.

[@HamRadioA2Z]

Hi. First, congratulations on the Tech and General! Second, thanks for watching! An external tuner may or may not be “required” or even “preferable”, depending on your setup. If you live where you can put up resonant antennas for whichever bands you want to work, then just the internal tuner or maybe even no tuner will be fine. If your antennas are 3:1 SWR or less on the bands you want to work, then the internal tuner will cover that just fine. If you have to operate where you have to use a compromise antenna and/or you want to work most or all of the HF bands, then you might need an external tuner. Sorry this is an answer that really isn’t an answer, but it really depends on your circumstances and goals.

[@furonwarrior]

I sent an email to MFJ, this tuner will work at full 200watts on FM/AM/Digital.

[@richardollins6079]

I am thinking of using the mfj-939 as a remote tuner at the antenna feed point. Do you happen to know the operating temperature range? I can't find it on the mfj site. Any data from your first hand experience?

[@HamRadioA2Z]

Hi Richard. I’m sorry, but I don’t know what temperature range it is good for. I suspect that it would be fine as long as you put it in an enclosure to protect it from direct sunlight and rain. Depending on how long the run it, you will probably want to use fairly heavy wire for power and ground so you don’t get too much voltage drop. I’ve heard that MFJ technical support is pretty good. You might give them a call and ask them.

[@johnedwinsnyder5082]

Tangental question--You mentioned your end-fed antenna with 9:1 unun. I am curious as to the length you have chosen for the wire.

[@HamRadioA2Z]

I have tried several different lengths. I've also tried different counterpoise lengths. There are a number of websites with recommendations. Palomar engineers sells some different options, but they also have a pretty good write-up on their website with various wire lengths listed if you want to build your own: palomar-engineers.com/tech-support/tech-topics/best-hf-end-fed-antenna

[@dougrea]

loving your videos! Do I understand correctly that there is no need power the tuner with external DC? Wonder if that same cable will work with my MFJ-998

[@HamRadioA2Z]

You are correct. The tuner is powered by the tuner connector on the radio. MFJ does make an Icom specific cable for the MFJ-998. It looks like they sell the same cable for the 939, 998 and several other tuners. So it looks likes it should work fine.

[@mikeramsey9747]

I noticed that with the LDG tuner that the SWR (green light) does not stay on when tuned.

[@TR6Telos]

I also have a 20m end fed with 9.1 unun out to a tree, super stealth, in a valley, and find 20m and 40m to be the best, but its possible to make contacts on all of the HF band. I thought my hf days were over when I moved here, but even with low propogation it works, especially if the other side has a 6 over 6 over 6, Ha.

[@HamRadioA2Z]

Hi. Absolutely! You can have a lot of fun with almost any antenna. Some more challenging than others for sure, but still fun. We have finally moved into a house on a little property, so I have an opportunity for larger antennas now, but I’ve managed to maintain some level of HF activity through several rental houses, HOAs, etc. Keep making those contacts!

[@jarrettmaryframe2278]

Thank you for this video. Does the Icom 7300 display the resultant SWR after a successful tune?

[@HamRadioA2Z]

Yes. As long as you have SWR as the selected meter. Or if you touch & hold the meter, it will display all of the meters. You can always see what your SWR is when you transmit.

[@jarrettmaryframe2278]

Thank you. A nearby ham with a 7300 and an LDG IT-100 demonstrated his rig to me. When the LDG got a successful tune, the "good" light came on. The question I had was what the SWR really was and what the LDG determined was "good."

[@defyke]

This video did help - thanks! Two newbie questions though: Will the SWR meter on the Icom reflect the tuned values (mine don't seem to change) and I bought the MFJ939 but there's nothing that says MFJ939i but I did get the Icom cable.

[@HamRadioA2Z]

The built in SWR meter is on the radio side of the tuner. So, yes you will see the tuned SWR numbers, not what the antenna is actually doing.

[@timothystockman7533]

I have an MFJ-939 and an IC-7100 ito an end-fed. However my tuner is located at the feed point. I use bias tees sp the power runs on the coax. Check my QRZ. --de N3TS

[@richardsaunders3082]

Does the “Tune” button on the 7300 automatically reduce the power level for tuning ? The 939 manual (quote below) says to keep power low, but it is unclear if the 7300 “tuning process” takes care of that ??? Likewise does the 939 tune button “tell” the 7300 to reduce power, tune, then return to previous power setting ? The 939 manual says: “The minimum power to tune is approximately two watts, with maximum SWR tuning accuracy occurring at tuning power levels of 10-20 watts.”

[@HamRadioA2Z]

Hi Richard. The answer to both questions is yes. I should have mentioned that in the video. When the 7300 goes into tune mode, it puts out a CW carrier at about 10 watts. This occurs either when you press the tune button on the rig or on the tuner. So it is perfectly safe for your 939 - or any other tuner connected.

[@WILLIAMPERRELLI]

Tom. I hv come more in line with the 939. What I would like to ask is, when connected and pushing the tuner button on the 7300, do I need to turn down the power from 100 percent to 10,20%, etc.? Or will the radio do it for me? Thanku again William

[@HamRadioA2Z]

When you press and hold the TUNE button on the 7300 (or on the 939), the 7300 will set the power level to 10 watts and output a CW carrier regardless of the current mode and power setting.

[@truthfilterforyoutube8218]

Hello Tom. I also live in a rental situation. How are you grounding the radio and tuner?

[@HamRadioA2Z]

I was able to drive a small ground rod next to the back of the house. I had that connected to the radio and tuner with a 6 or 8 gauge wire.

[@andrevanklaveren3628]

I noticed that you have a counterpoise attached to your match box. How long was your counterpoise? Excellent video on external tuners...helped me a lot in choosing my new radio and tuner. -KD9RFE

[@charlesolinda7173]

Tom, Thanks so much for making these informative videos! I have a question about the "auto/tune" button (R/lower side) ... do you cover that in one of your videos? Also the steel deck chair looks identical to the one my Neighbor gave me many moons ago. Best 73, Charlie, N2SRQ.

[@HamRadioA2Z]

Hi Charlie. Thanks for the kind words. I think I did cover AutoTune in a CW video, but it was a few years ago. I’ll have to figure out which one. In CW mode, that button will adjust your receive frequency to put you right on the carrier frequency of a CW signal. If the band is real crowded with multiple CW signals, it doesn’t work so great. It has no way of knowing which signal you want to tune to.

[@miker1473]

My 939 communicates the tune status on to the face of the 7300. There is an internal set of jumpers in the 939, that has to be set for icom rigs.

[@keithwinkler736]

What are the setting please? I cannot find in the user manual.

[@miker1473]

@@keithwinkler736 pages 9-22 cover the internal jumper settings, and interface cableing, for each brand of radio supported. The easiest way of avoiding this, would be to purchase the 939 model intended for your radio. In the case of the 7300, it would be the MFJ 939i. Then it comes pre-set for the radio, along with the proper interface cable.

[@keithwinkler736]

@@miker1473 Thank you Mike R

[@miker1473]

@@keithwinkler736 but.....you can always use the plain 939 in a stand alone mode. Just use the DC power cable to power it, and, hit the tune button on the face of the tuner to tune. You can also set the 939 to initiate a tune on its own, if the sensed swr is above a certain level. It actually works pretty good for being an mfj product.

[@markmarquardt8016]

Can you please show me where you have grounded the 7300? I did not see it in the manual. Thanks.

[@HamRadioA2Z]

Hi Mark. You can find the ground screw between the antenna connector and the power connector on the back of the radio. You can find it illustrated on page 1-4 of the manual.

[@TheDieselman17]

If I'm using a alpha delta dx-cc as an inverted v up 30 feet do you think I will really need an external tuner or will the internal tuner be fine?

[@HamRadioA2Z]

Hi Aaron. According to Alpha-Delta's website, that antenna should be resonant on 80, 40, 20, 15 and 10 meters. So it shouldn't even need the internal tuner on those bands. If you want to use it on the WARC bands or 160 meters, it's hard to say. The radio might be able to tune it on a few of them. The easiest and cheapest way to find out is to try it. Just try tuning with the internal tuner at the top and bottom end of each band you want to work and see. If the internal tuner doesn't cut it on a band you really want to work, you can always add an external tuner.

[@WILLIAMPERRELLI]

Another nice video Question. With the mfj hooked up, can u press tune on either the radio or the mfj to engage tuning? Lastly, I saw u tune up on 160. Is ur wire an 80-10 or a 160-10? Thanks William

[@HamRadioA2Z]

Yes. With the MFJ,, LDG, or any tuner made to interface with Icom radios you can press the Tune button on the radio or on the tuner. When I made that video I had a 53ft end fed random wire. It wasn’t very efficient on 40 or 80, let alone 160. I just wanted to see if the tuner could match it on 160.

[@WILLIAMPERRELLI]

@@HamRadioA2Z Thanku for replying! Were you able to reach anyone on 160 or was it just matching and thats it? The 7300’s internal tuner is too limited, even on the high end of 80 meters(3900-4000. With emergency mode(10:1 I believe)I can indeed do it. With my 140 foot end fed and a good external auto tuner, I was hoping for just a bit of 160 meters. If so, do u consider the mfj 939(great reviews) or the ldg ? Thanku again William

[@chrismarren9308]

hi tom, if you change the 9:1 unun for a 49:1 transformer you should be able to tune the antenna with the int tuner

[@HamRadioA2Z]

Hi Chris- That may or may not be the case. A 49:1 xfmr is typically used on a half-wave end fed antenna, not a random. A 1/2 wave end-fed antenna has an impedance of 3000-4000 ohms. So the 49:1 transformer brings that down to around 60-80 ohms. So it’s much better than 2:1 SWR and doesn’t really need any tuner. The internal tuner is good for antenna impedances from about 16 ohms to 150 ohms. With a random length end-fed, the antenna impedance will be a few hundred ohms or less on a lot of bands. So a 49:1 transformer would bring that well below 16 ohms and it would be out of range of the internal tuner at the other end of the scale.

[@martindrury9740]

Hi. Can I ask what was the SWR before you used the auto tune? Thanks. M7MGD.

[@HamRadioA2Z]

Hi Martin. With that antenna, it varied depending on what band I was on. I have moved from that location and I don’t have detailed notes on that antenna, but it was anywhere from about 2:1 on the best bands to about 5:1 on the worst bands.

[@ve3cwq47]

Hi Tom, great video. I'm curious, how long is your random length end fed and is it grounded at the balun?

[@HamRadioA2Z]

Hi. Thanks for the kind words. I had two. One at a house we rented and one at my father-in-law’s. One was 53’ and one was about 135’. I did not have it grounded at the unsung and I also didn’t use the coax as my counterpoise. I had a separate counterpoise wire at the union and I made a coax choke balun right at the unun. I’m not a big fan of having the coax shield radiate (but many people operate this way with great success). Palomar Engineers has some good information about end feds on their website. They even include DIY unun plans if you don’t want to by their stuff. They provide multiple antenna length suggestions for different band combinations. You can find that here: palomar-engineers.com/tech-support/tech-topics/best-hf-end-fed-antenna. 73, Tom

[@ve3cwq47]

@@HamRadioA2Z Thank you very much for the link Tom. Excellent resource. I have the Earchi 9:1 unun (who doesn't) and a roughly 124' long wire. I'm on the second floor of a six story midrise with a 75' LMR-240 coax feedline to the roof. No grounding. Definitely getting some RF down the coax at anything above 10-15 watts out of my 7200 and LDG tuner. It was playing havoc with the USB cable between the radio and computer. I threw on a couple of clam shell ferrite chokes and that helped quite a bit but I keep the power low to reduce the risk of interference with my neighbours. My QTH suffers from local QRM, both inside and out, and the noise floor above 20m is pretty challenging. I need to find myself a place in the country.

[@alexanderneumann6664]

just saw your video. many thanks. I see that this dates some time back. Any new insights since then?

[@HamRadioA2Z]

It has been quite a while since I did that video. I’ll have to look at it and see if it needs any updates.

[@dennymagdule4372]

Can you please explain to me the grounding of the tuner and the radio with a tuner. How did you connect the grounding wire? My thanks for your reply.

[@HamRadioA2Z]

You should ground both your radio and your tuner to the same grounding point with a wire from the ground terminal on each to the common point. The ARRL has a good basic explanation of grounding here: www.arrl.org/grounding. They also offer a book: Grounding and Bonding for the Radio Amateur by: Ward Silver. It is a great reference.

[@therailbirdz6398]

Hi Tom; I've had my IC7300 since April 2019 but did not find your videos until last week. They have been extremely helpful and are well done, thanks for doing this. I've had some issues with SWR actually shutting down the 7300 during the tuning process. I have 3 sources to read SWR; the IC7300, a PWR/SWR meter downstream from my amp, and my LDG AT600 Pro II tuner. In some cases the SWR on the IC7300 shows a different value than either/both the PWR/SWR meter and the tuner. What is that? Thanks Frank W1ZAH

[@HamRadioA2Z]

Hi Frank. First, thank you for the kind words. You didn’t describe how your setup is wired, but I would expect that it is 7300->Amp->Tuner->Pwr/SWR Meter. There are multiple things going on here. I’m going to make a couple of assumptions- I assume that when your amplifier is off it has a bypass relay so it is effectively out of the circuit. I am also assuming that when you have the tuner tune, that the amplifier is off/bypassed at that time. It looks like that AT600 supports the Icom radio tuner interface. Are you using the optional interface cable to the molex connector on the 7300? If so, then I’m not sure why the 7300 would shutdown while tuning, unless the tuner itself is detecting too high of an SWR and it is stopping the tuning operation. Does this only happen on certain bands? Regarding the different SWR readings- It is important to remember that each meter is looking at a different part of the antenna system. Amplifiers are designed to present a 50 ohm load to the connected transmitter. So when your amplifier is online, the 7300 should see a 1:1 SWR, or pretty close, no matter what is going on past the amplifier. If you have things connected in the sequence I described (which is the proper sequence, in my opinion), then your PWR/SWR meter is going to see the SWR at the coax coming into your shack. So if your antenna system is 3:1 on some particular frequency, then your PWR/SWR meter will see a 3:1 SWR on that frequency even after the tuner is engaged. We all call them “tuners”, but remember that they don’t actually “tune” the antenna, they just keep inserting L/C elements so your antenna looks like a 50 ohm impedance to the transmitter (or amplifier). I believe the SWR meter in the tuner is showing the the SWR at the transmitter connector. So it will show a 1:1 SWR when it is done tuning. If you have the tuner bypassed, then its SWR display should be pretty close to what your PWR/SWR meter shows. If you have the amplifier and AT600 both set to bypass, than all 3 of your SWR readings should be pretty close. Hope this helps. 73, Tom

[@chuckmcdermott7053]

I notice when you hit the tune button on the radio the tune light comes on but the mode still says USB; does the radio stay on SSB during the tune, or does it change to am, fm, or cw to accomplish the tune. I’ve been changing to CW during the tune, and then back to SSB, but maybe that is not necessary. Any thoughts?

[@HamRadioA2Z]

The radio automatically puts out a CW carrier at low power when you start a tuning sequence. It doesn’t change the displayed mode or power level. You don’t need to change it to CW before pressing tune. Whatever mode you’re in and whatever power level you have the radio set to is fine.

[@BillPfaffenberger]

Tom, Great series. Did you have to remove any jumpers on the inside of your 939 to get it to work with the 7300? I just got another MFJ-939i and the 7300 tuner button doesn't operate the external tuner.

[@HamRadioA2Z]

Hi Bill. If you got the 939i, you shouldn’t have to change any jumpers. The “i” model is supposed to be preset for Icom radios. That is the model I have and I didn’t have to change anything for it to work with my 7300. If you bought one used, maybe the previous owner changed the jumpers to work with a different brand. I believe all of the 939’s are the same unit with the jumpers preset for each radio brand. The instruction manual shows the correct jumper settings for each radio brand.

[@BillPfaffenberger]

@@HamRadioA2Z Tom, this is my second 939 so I suspected that the interface cable was bad. So I used the cable from the 939 I use with my IC-7100 to test my connection to the 7300. The 939 worked as expected with a properly wired cable. Bottom line, MFJ is sending my a new interface cable. THANK YOU SO MUCH FOR GETTING BACK TO ME.

[@keithmarshall8478]

What power do you set on your icom if using the mfj and also internal tuner

[@HamRadioA2Z]

Keith, if you connect an external tuner, made for Icom rigs to the tuner connector on the back, it will disable the internal tuner. You don’t need to set the power during tuning. The radio will automatically put out a low power carrier when you press the tune button, regardless of the power or mode setting.

[@Aleziss]

while you tune with an external tuner, does your SWR meter on the 7300 works ?

[@HamRadioA2Z]

Hi. Yes, the SWR meter on the radio still works when an external is connected. HOWEVER, it is important to remember that the SWR meter in the radio is displaying the SWR it sees on its connection to the tuner. So, if the tuner is able to match the antenna, you're always going to see an SWR of close to 1:1. To see the SWR of the antenna, you will need to remove the antenna tuner from the circuit. The MFJ-939 tuner bypasses itself when it is powered off. You can bypass the tuner in one of 3 ways-- 1) Turn off the power button on the front of the tuner. 2) When the TUNE indicator is on, briefly press the tune button on the radio. This will turn the TUNE indicator off and bypass the tuner. 3) Like with 2) above, briefly press the tune button on the tuner. It should do the same thing. If you want to check the SWR of your antenna, MAKE SURE you turn the power on the radio down to 10-15 watts before you put out a carrier. The radio only automatically lowers the power when you use the Tune button.

[@k3xq856]

Having a similar setup, I have a question. I also utilize headphones quite a bit and have found it to be a real eye opener after a long qsl with the volume up, change freqs, then hold that tune button...without remembering to turn the volume back down. I think it's giving me tinnitis hihi. I've tried searching all over in addition to playing with radio settings but haven't found anything. I thought it'd be as simple as a monitor setting, I'm stumped. Is there a way to disable that tone through your speaker/headphones when tuning with an external tuner?

[@HamRadioA2Z]

Hi- I went and tried this on my 7300. You are absolutely right! There doesn’t seem to be any way to adjust the tuner side-tone volume separately from turning the volume control down. And, it does seem to be pretty loud compared to receiver volume. The “Beep” volume settings and whether Monitor is on or off does not seem to affect this. If I find anything else that might change it I’ll let you know, but for now I would call this a software bug - or at least an oversight.

[@k3xq856]

@@HamRadioA2Z Well, I'm glad that it wasn't something simple and just making a fool out of me then.

[@joecraft4409]

Tom, is there a difference if one uses the "tuner" button on the IC7300 or the 939?

[@HamRadioA2Z]

Nope. They both do effectively the same thing.

[@roypinkney4432]

Hi this ROY Ve2uy , love your comments for the IC-7300. Wondering if it would work with an SGC smart tuner? I don’t have a 7300 , wish I did. I have a Kenwood TS-480 HX. I did install the tuner at the antenna and it’s great. By the way the antenna that I’m using is 48’ long and only at 24’ above ground it’s home brewed. The original was on the internet and it is invention of a fellow in the UK. G7FEK Limited space antenna, look it up very interesting find. I have just rebuild it today and getting 1.2 to 1.7 across all bands without the tuner but I keep in inline just the same. Cheers Roy

[@HamRadioA2Z]

Hi Roy. I have an SGC-239 that I've had for years. It works fine with the 7300, just not automatically. There are a couple people out there who have made "tune plugs" that plug into the tuner connector on the back of the radio. They basically fake the radio into thinking there's a tuner connected. Then you can push the TUNE button and the radio will bypass the internal tuner and put out a low power carrier so the SGC tuner can go through the tuning sequence.

[@billjobes1851]

Tom, I use the MFJ tuner with my IC-7300. When I QSY to another portion of the same band, the tuner drops out, seemingly randomly, and returns to functioning when I return to the frequency I was at when I tuned the radio. If I stop and tap the Tune button on the radio when it drops out, it re-tunes to my location, and signals return. Is there a way to know with more precision how much of the band is 'tuned,' once a particular frequency is tuned? Are there Menu settings that affect this? Thanks.

[@HamRadioA2Z]

How much of the band any “tune” will cover is heavily dependent on the antenna system that is connected. I am not aware of any simple way to check this without sampling SWR at various frequencies. In your case, you say “drops out” and “signals return”. This sounds much more drastic than I would expect. As you move away from the frequency you tuned, the SWR will rise, but in receive, you really shouldn’t notice a significant difference in signals unless you are changing bands. I suggest that you look for intermittent connections in your setup or maybe something intermittent inside the tuner.

[@michaeljbrennan3728]

I have a MFJ 929 that has a J4 jumper installed. Do I have to remove it before using the external tuner? Thanks in advance.

[@HamRadioA2Z]

Hi. I’m afraid I don’t have any experience the 929. I have the 939i tuner. I’m not sure how similar or different it is from the 929. The 939 series is available as i, y, or k versions that come preset for Icom, Yaesu, or Kenwood radios. I don’t know if the 929 has similar options.

[@WILLIAMPERRELLI]

Hi I noticed that you were able to tune 160 meters. What length of wire are you using? I hv a ‘ My antennas’ 80-10( 134’) end fed and I cannot tune 160. Thanks William

[@HamRadioA2Z]

I think I had about 65 ft of wire when I made that video. Remember that the length of a counterpoise wire, if any, and the length of your coax will also affect how it tunes on any given band. Also, don’t confuse “tuned” with “works well”. I never worked anyone on 160 when I lived at that location.

[@scottgoodrich5825]

Thanks for this. On page 7-2 of the 7300 manual it says, “Be sure to turn OFF the internal antenna tuner before connecting the external antenna tuner.” This is confusing to me. (I have the LDG IT-100 autotuner)

[@patpowell3050]

Thank you for the very educational info on the 7300. Have had the 7300 for a few months and so wish I had watched all your series already. I've gone thru #14 just tonight PLUS #41. So far my antenna tuner (for my non-perfect antenna) is a Heathkit SA-2060. Although it has done a great job, I wished to go "automatic" and wanted the MFJ 939. Availability has been NIL so I finally broke down and purchased an MFJ 929 (and Icom cable) which will be here SOON. Do you know if it will be basically the same operation as with the MFJ 939?

[@HamRadioA2Z]

Hi Pat. Thank you for watching and for the kind words. Yes, the MFJ 929 should operate in the same way with the 7300. It's actually a nicer, fancier tuner. It gives you a separate SWR and Power meter display, plus it supports 2 separate antennas.

[@patpowell3050]

@@HamRadioA2Z It came in and got it hooked up this weekend! Super easy to install and it is an outstanding tuner as you say. Once again THANK YOU for your time in putting these videos together so nicely. I'm new to the HAM world but getting into as many of the different ways to appreciate it so your more advanced subjects are still on my "to-do" list!

[@n1kkri]

Did you ever try the MFJ tuner on 6m? What is the min power required to work with that MFJ? If you tried 6m with the other tuner how well did it work? Did you ever try the Emergency Mode with the IC-7300 for a wider range of matching?

[@HamRadioA2Z]

I have used the MFJ tuner on 6m. It seems to work okay up there. The MFJ manual says that the minimum power for tuning is 2 watts. I have played with Emergency mode some. It seems to work as advertised and allows the rig to match SWRs higher than 3:1. I haven’t had a need to use it regularly since I have the MFJ939 tuner.

[@n1kkri]

@@HamRadioA2Z Thanks for this info. I wonder why they don't advertise the MFJ tuner for 6m. I have a MFJ-993 and it doesn't work very well on 6m. Thanks also for the Emergency Mode info. My brother in law has the 7300 and wants to get on 6m.

[@raygami]

Can the 939 turner ground be connected to the Icom 7300 ground? I mean to put a direct cable from the transmitter to the coupler? Thank you

[@HamRadioA2Z]

It can be connected that way, but that is not ideal. You should connect your 7300, the 939 and any other equipment in your shack to a single, common grounding point. The ARRL has some answers on their website here: www.arrl.org/grounding. They also put out an excellent book on grounding that you can find here: home.arrl.org/action/Store/Product-Details/productId/133989

[@raygami]

@@HamRadioA2Z Thanks!!

[@N4KRX]

Very good video! Over the past several years I have bought and sold several IC-7300's. I have always been puzzled as to why Icom doesn't go into more detail about using external tuners in the manual. You would think there would be a setting you would have to disable to bypass the internal tuner if using and external tuner. I have always wondered if both the internal and external tuners were both "TUNING" when using the tune button on the IC-7300. The best I could tell, just as you mentioned, the radio senses the external tuner and bypasses the internal tuner automatically. I am using an LDG AT-100ProII Autotuner with the LDG Icom cable on my IC-7300 with great success!

[@scottgoodrich5825]

I had that same problem. I just figured if I didn’t hear the internal tuning noises inside the 7300 and I heard my LDG working than all was well. 73, W2LTD.

[@gregrandolph2845]

Yes, I was trying to understand this also; and the IC-7300 manual doesn't mention how the external tuner control works! I am using a Elecraft KAT500 tuner.

[@apnewz]

Very good video, Informative to me and God will give you your own house where you can set up a big shack and many antennas in the backyard, ❤ from, George, VU2XFD

[@Silverhawk1776]

If you have a high-SWR antenna system that a MANUAL tuner that can only get down to 2.5:1, could you then use the 7300's internal tuner to finish the match?...Or would two tuners together create more issues?

[@HamRadioA2Z]

There might be some interaction between the tuners. However, the output of your external tuner will look like a 2.5:1 antenna system to the 7300. So, yes. You could get a 1:1 (or close) match at the radio. The problem is that a lot of your RF is being turned into heat in the internal tuner, external tuner, and mismatched coax going to the antenna. So, although it would work okay from the radio's perspective, it probably won't be a very effective antenna. Always remember, a 50 ohm dummy load presents a 1:1 match to the radio too, but you're not going to work a lot of DX with it.

[@stevebennion]

If you are using the external tuner and the IC7300 is at 100 watts, does pressing the tune button on the 7300 reduce power to ~10 watts for tuning or do you have do to that manually?

[@HamRadioA2Z]

When you’re using a tuner connected through the 4 pin tuner connector, it is automatic. When you push the tune button the radio will put out a solid Cw carrier at about 10 watts regardless of what mode the rig is in or what the power level is set to.

[@stevebennion]

@@HamRadioA2Z Thank you so much for the very quick reply. I thought that might be the case because now while I’m waiting for my automatic tuner to arrive I’m using the Click2Tune which does that same thing through that Molex connector. Your Videos are very helpful and appreciated thank you

[@ronsmith6662]

Can you still see your swr reading using the 7300's swr function.? Great video Tom. I'm looking at getting an MFJ 939 i.

[@HamRadioA2Z]

Hi Ron. The SWR function will still work, but with an external tuner connected, unless you bypass it, you're just reading the SWR between the rig and the tuner. And, likely as you keyed on each different frequency, the tuner would try to start tuning if you were too far away from the frequency you originally tuned up on. So, the shorter answer is that it will work, but it won't really tell you anything very useful.

[@ronsmith6662]

@@HamRadioA2Z Thanks so much Tom. Exactly the answer I needed. VE3SDQ.

[@WILLIAMPERRELLI]

Tom hi I just received my 939 today. Another question(s). Are you reducing power on the 7300 before tuning the 939? I know the 7300’s internal tuner automatically does this for you. As for the 939’s auto/semi auto settings(gets a bit confusing) and the ‘sticky mode’, how are you setting these? Thanku again! I really enjoy your videos. A really nice teaching voice😃. William

[@HamRadioA2Z]

When the 7300 senses that an external tuner is present, it will set the output to 10 watts and cause the external tuner to tune when you long press the TUNE button. The internal tuner is automatically bypassed. This all assumes that you have the tuner interface cable plugged into the tuner connector on the back of the radio. With the interface cable connected, you don't need to worry about the 'sticky mode'. The TUNE button on the radio will key the radio and activate the tuner. I know the 939 has memory banks for multiple antennas and several options for how it operates. I frankly have not used any of those features. I don't currently have multiple antennas coming into my shack. When I take the tuner to other locations, I just let it re-tune on the different antenna. It is fast enough that I don't find it worth it to keep track of which memory bank is set for which location I operate at. Hope this helps. Thanks for watching and thanks for the kind words. Tom

[@WILLIAMPERRELLI]

@@HamRadioA2Z Thanku for this info. It answers my questions!! Best William

[@JPDW3072]

Hi, what kind of antenna one can use that is best for Icom-7300? Thanks..

[@HamRadioA2Z]

Hi Ellob. That is a very very big question. If you ask 10 hams that question you will probably get at least 20 answers. The answer also depends on what kind of operating you want to do, what your budget is, and where you live. An off-center fed (OCF) dipole is a good, general purpose antenna that will let you work multiple bands with one antenna and only using the tuner built into the radio. If you have very limited space, there are also multi-band verticals that require very little yard space. Although most of these will require a radial system of some sort. I hope this helps.