IC-7100 Accessory Audio Squelch Circuit

This is just a quick to share some success I just had building an audio switching circuit to squelch the audio coming out of the ACCessory connector. One of the quirks with the IC-7100 is that the audio out of the accessory jack does not go through the squelch circuit. That means that on a VHF/UHF FM frequency, you would hear constant white noise/static if you pipe this audio to your car stereo or any other amplifier system.
The Accessory connector does have a pin that tells you if the squelch is opened or closed. So I connected the squelch output to the audio switch and piped that output into my truck audio system. Now I have squelched audio!
I intend to make this into a full project video in the future.
I am considering designing a printed circuit board for this circuit. Please leave a note in the comments if you would be interested in buying a circuit card or maybe a complete kit for this circuit.
The audio switch is based on information I found on this website:
neatcircuits.c...
Please check out the companion website for this channel here: a-2-z.tech/
Thanks for watching!

[@fredbook1]

Count me in for both! I am working on a IF tap that feeds to my cheap android head unit for a 7300 feel for my 7100

[@the1spyderryder]

Hi Tom . It is good to see hams designing electronics. There are too many doing nothing but unboxings and reviews. I would definately be interested in a couple boards. I would like to see you do a video on recording things for play back on the 7100 like recorded CQ calls and things like that. Coy Hilton AC0Y

[@HamRadioA2Z]

Thank you for the kind words Coy. Check out this video for some information on using the voice recorder: kzbin.info/www/bejne/hn_KZJyQp6qBbbM

[@markendicott8722]

Tom, I use the audio jack in the remote head with the SP/Phones switch in Phones (headset) position to connect to amplified speakers on my desk. Squelched audio is of course available there and interfaces nicely with the amplifier and sounds great. Your audio gate project is a good little project too, thanks.

[@HamRadioA2Z]

Hi Mark. Yours is the 2nd comment about using the speaker jack. In the other one, he used the speaker jack into his car’s auxiliary input and it works fine for him. They’re both definitely good options and it depends on personal preference. I did come up with a couple of drawbacks to using the accessory jack audio on my trip to Huntsville. I’ll be doing a video with an update on the circuit and what I’ve found using. Should be coming out soon. 73, Tom

[@emailuser3869]

Good work! Fine business.

[@drillkjh]

Tom I'm very interested in this. I would definitely purchase one from you.

[@srice257]

Tom, Thanks for all your informative videos! I would be interested in a kit for the Squelch Circuit, I enjoy how you think....

[@timslink]

Yes definitely

[@leilaniwilds188]

Yes interested in adding this to my 7100. Dennis

[@cmndo9741]

Thanks, Tom. I'd be interested in a kit to put this together for my vehicle.

[@Davidjb37721]

Thanks

[@alansteiber3031]

I would be interested also

[@CrittendenIV]

Very cool. I would be interested in an assembled unit (or kit if only way). Thank you very much for your expertise. :) KJ7NUX

[@dancoursey5447]

I have to check and see if there is an automatic jack into my 2018 Tacoma radio

[@drb141719]

Hi Tom, did you manage to get any further designing the pcb version. If you did do you have any available? Regards, Daz de M0TTY

[@pedromorillas6535]

I’m interested in buying a kit

[@dave-wk4t]

Very nice. I’m closer to fixing the injector noise. I’ll let you know.

[@HamRadioA2Z]

Please do. I’ll be curious to know how you do it.

[@TheScottClifton]

Tom, why didn’t you just use the rigs external speaker output? I have my FT-857 plugged into my car’s aux input that way. It works fine without even installing a shunt load resistor or attenuator.

[@HamRadioA2Z]

Hi Scott. I plan on covering that topic in the full video. Several reasons. One, you already mentioned, is that I would need to add (I had assumed) a load or attenuator of some type to keep from getting distortion. I’m surprised you didn’t need that. Do you have the volume turned down really low? The 2nd reason has to do with the volume. The Accessory connector output provides audio at a fixed level. This way I don’t need to keep re-adjusting the audio level when I switch from radio speaker to vehicle stereo. Finally, in my case, I already have an external speaker connected to the radio and I switch back and forth between that speaker and the truck audio system depending on whether I’m actively working on the 7100 or I’m listening to something else in the truck and want to listen to the 7100 in the background. I can’t listen to 2 sources at once with my truck system. Great question. Thanks for watching!

[@TheScottClifton]

@@HamRadioA2Z the volume is at about 10 o’clock to match the level of the AM/FM/XM sources. I have thought about building an audio combiner, basically a mixer with 1/8” mini ins and outs, to support more than one radio’s audio. A simple fixed 10k load and series resistor isolation combiner to a combined output. You have to realize that the aux inputs are expecting to see headphone/speaker outputs from our players, so it’s not driving a high gain input. I would probably promote the use of a series 4.7uf Cap, just to provide protection for the general publics use. I’d just use the receiver’s volume controls to adjust each of their levels.

[@HamRadioA2Z]

Hi Scott. I know that the aux-ins are designed primarily for smart phone and MP3 player headphone outputs, but I figured that connecting an external speaker output would have been a bit much for it. I would think that a headphone output is a lot closer to line-level outputs. You make some good points. I will probably mention these when I get the full video put together. Thanks again for your comments. 73, Tom

[@vicmiller7191]

Is the icon 7300 the same way? I like the idea of the PC board idea to make the mod easier too. Thanks for sharing...Vic de KE8JWE

[@HamRadioA2Z]

Hi Vic. The IC-7300 does not have this problem. On the IC-7300 the Set menu item for squelch enables or disables the squelch for BOTH the USB audio output and the ACC connector output. The 7300 also has an additional setting that lets you select whether you want the keyboard beep sounds to be on the ACC audio. On the 7100, the ACC jack and USB audio does not include keyboard beeps and there is no option to enable that. So this circuit isn’t needed for the 7300.

[@vicmiller7191]

@@HamRadioA2Z Thank you for the quick reply, I have considered getting a 7100 for portable use and your method would work quite nicely and I can keep my 7300 as my base station. Thx, Vic de KE8JWE

[@Hindukushsailing]

Hello new sub. Could you comment on setting up and using a Ham and SSB capable rig on a sailboat. I am a newbie.

[@HamRadioA2Z]

Many people operate marine mobile with great success. The water makes a great ground plane for your antenna. Your antenna options will depend on how big the boat is. I know that running a wire antenna from the bow or stern up to the top of the mast (with appropriate insulators at each end) is a pretty common HF setup. You will have to use a tuner with this arrangement if you want to operate multiple bands. The sailboat will have some type of electrical bonding system to the water. You will want to connect that to your station grounds. If it’s not your sailboat, you can tie a weight to a copper strap and throw that in the water with the other end connected to your equipment. The Maritime Mobile Service Network may also have some tips and other resources that might be helpful. You can find them here: www.mmsn.org/. Hope this helps. 73, Tom

[@truevinetoday1398]

Huel K5TVN...great video ...well did you design it

[@HamRadioA2Z]

Hi. Thanks! I based the squelch circuit on a simple audio mute circuit I found online. I’ve made some additional changes to the project and ordered some updated boards. I’ll be doing a follow up video when those come in.

[@JJ-el8li]

I am interested in the schematic only so I can build this myself.

[@HamRadioA2Z]

Hi. I have an update video on the mute/squelch circuit coming out shortly. I'll be posting the schematic on my website. there will be a link with the video.