#31 IFR 1200 Service monitor problems and repairs

#31 IFR 1200 problems and fixes.
In this video we take a look inside the IRF 1200 Service monitor.
We will address the low output issue from the T/R jack and have a look at the termination dummy load failure. We then pull
the scope/analyzer unit and repair the dirty switches.
My website
gokarters.com/s....
KG Electronics
www.kgelectroni...
IFR 1200 service info
www.repeater-bu....
For great electronic learning tutorials:
Mr. Carlsons Lab
www.youtube.co....
TRXBench
www.youtube.co....
EEVBlog
www.eevblog.com...

[@RossDuClair]

I have congratulate you for this repair. I have a 1200ss with a problem of LOCK and dirty wafer switches. You are absolutely fearless taking on desoldering the switches from a double sided board. Your patience and skill are remarkable.

[@TheRadioShop]

Thank you very much for the kind words. At times you have to dive in with both feet. I am going to do a complete rebuild on one of these units soon.

[@ve2zzz]

Especially with the blue double-clad PCB's... They are very fragile....

[@Jeff-zy1pb]

Hi Buddy, I had the same issue with the trace jumping due to dirty switches. I had watched this repair and knew one day I would have to buckle down and do it like you did. Last week the scope went out of focus and I couldn't bring it back in with the adjustment knob - the time had come... I did your repair to the switches which went like clockwork - the only thing I added was to use chipquik to make the switches easier to unsolder without using as much heat, great stuff. The focus problem turned out to be a resistor had gone high value on the scope power board (the last of the 820Kohm in series on the focus HV line) which is right under the board with the switches so easy to get to. Swapped it out and reassembled everything. Thanks for motivating me to dig in there, its back up and all running well! 73 AC2PL

[@TheRadioShop]

Thanks for sharing that. This is the type of success stories I like to hear. Had the exact same thing with the resistor on another unit. I also will be doing another repair very soon on a super S. Thanks for the comment

[@kimmoles2492]

Excellent video. You're definitely not just a parts changer. Taking those switches off the board, takin em apart, cleanin em, which fixed the problem was impressive. Thanks for posting these videos. I really enjoy them. Especially the test gear and anything " tube-type". Chuck AB8FI

[@TheRadioShop]

Thank you Kim for that kind comments. I only use common sense approach to my repairs.

[@ebtest7172]

A terrific job, give yourself a big pat on the back! I have been experimenting with a IFR 1200 AM/FM A/S and am getting ready to read and write the U67003 and U67004 EPROMS, your video makes me much more confident. Thanks for a great informational video!

[@MrCarlsonsLab]

What a great video Buddy! We share similar thought's on those radios you mention. Nice tour on the inside of the analyzer as well. WOW!.... $200 for that resistor, that's just crazy. I hope it at least comes with a swept response sheet (ya right) I notice my R/S signal gen has the same modular build, almost looks like you could module swap between the two (it looks that close) I look forward to your next video! Thanks for the kind mention as well !!! Paul

[@TheRadioShop]

+Mr Carlson's Lab Thanks for the kind words Paul :) And yes, I am bit finicky about  certain made radios. And you are right about that resistor. Most expensive one I ever seen. I have searched for 2 years trying to come up with something cheaper. Nada, I am trying to vision you signal gen, model number? I am sure I have seen it with that vast amount of gear you have. going to have to go back and search your vids... like to see the schematic and layout to compare with. Anyway I am off till Monday so looking at what is next on my list to video. Thinking about a good ole boat anchor. TS-520 perhaps? And as always I am going to throw you or Peter in there somewhere;) Thanks again and looking forward to your next one also.

[@MrCarlsonsLab]

Thanks Buddy! I Vote for Peter! :^) The signal generator is a Polarad SMPC. The R/S SMPD service manual crosses. The file is almost 400MB large (part 1) easily found on line. On my bench, it's located on the upper half towards the curve tracer, right below the grey spectrum analyzer I look forward to what ever you choose to fix and do a video on. The TS-520 is a nice mix of technology, solid state and tube at the same time. I have been working on an in-depth video for months (In my spare time) hopefully it will be done soon.

[@TheRadioShop]

+Mr Carlson's Lab Will check it out Paul, Thanks. I love test gear.. That is a large file lol. Cool, the 520 and HP volt meter are next on the list :) Cant wait to see that video you mentioned. Have a good one my friend.

[@TRXLab]

+The Radio Shop Looking forward to what ever you record!!

[@TheRadioShop]

+TRXBench Well, I recorded 2 videos this week end. Problem is I am very sick and the voice sounds terrible. Going to try and edit them tonight and get them posted. In the mean time I see you have uploaded. Going to watch.

[@mikesradiorepair]

Don't you just love working on combo units. Took me almost a week to fully recap my Stabilock 4040 when I first got it. One suggestion. Get a bottle of Caig Deoxit Shield S100. It comes in a little nail polish type bottle with a brush. The S100 has no solvent, its 100% product. I use it on this type of rotary switch all the time and love it. I think the bottle I have now is close to two years old. A little goes a long way. Not only does it prevent future oxidation but it also lubricates the contacts and helps to prevent then from wearing out. Mike

[@TheRadioShop]

+MikesRadioRepair .CBRadio Great suggestion Mike. You cannot beat that stuff. In fact I need to order more. I use it on all my boat anchor rigs like band switches. Thanks for bring this to our attention. I bet that recap was a job.

[@mikesradiorepair]

+The Radio Shop A job to say the least. The one huge advantage of the Stabilock chassis design is its very easy to pull all the modules. Basically each module just slides in the back and is retained by two thumb screws. The modules each contain two or more PCBs. Its a pain because there are just so many caps in it. Whats worse was the caps are almost all low profile and there is really no room to use one that's close in size. Its either the correct physical size or it just isn't going to fit. Ended up ordering most all of them because most of what I stock was to large. Made sure I got the best money could buy long life low esr caps because I don't ever want to have to do it again. Hopefully they will be good for at least another 25 to 30 years. Get started on your HP VTVM yet? Mike

[@TheRadioShop]

+MikesRadioRepair .CBRadio I hate it when modern day components don't fit.. At least you should be good to go for a while.The TS-520 and the HP are next. maybe this week end.

[@patricklozito7042]

It's an honor to watch you work. Thank you so much for sharing all this. I just purchased an IFR1200 and it is invaluable to be able to see this. Very grateful. All the best.

[@DextersTechLab]

Nice fix, too many people would look to replace a switch instead of just taking it apart and cleaning!

[@TheRadioShop]

+DextersLab2013 I searched for a similar switch but have not found one as of yet. Afraid they were custom parts just for these units. At least they are a bit serviceable, And as long as the spring contacts are good one may could etch a new wafer... Thanks for stopping in my friend.

[@jeffwallach7533]

Great video! Been doing some minor (easy) repairs on my IFR 1200S for past couple of years...this is a great instructional video...thanks for all of your efforts for the Ham community! Jeff N5ITU USAF Civil Air Patrol COMM Officer

[@TheRadioShop]

+Jeff Wallach Thanks Jeff for the wonderful comment. There is just not enough information out there on these units so I try and share as much as I can on them. A lot of folks are just scared to crack one open and poke around. But if there is information available this helps and wish others would share. Thanks again commenting and stopping by. I will try and post more as time goes on.73Buddy

[@jeffwallach7533]

+The Radio Shop Thanks! My latest challenge is a bad FOCUS on the scope....nice, bright trace, but over the past few years the FOCUS has been going out...have to check the Service Manual to figure out if it is a bad capacitor...probably a well known issue....Jeff

[@TheRadioShop]

+Jeff Wallach Yes that is from a bad cap. Also check the resistors in that circuit. If cracks it will put a carbon burn onto the pcb. The supply board is directly under the crt. When checking the caps look for high ESR.

[@jeffwallach7533]

+The Radio Shop ..Wonderful, thanks for the tip and heads up...is that are difficult to get to>?

[@TheRadioShop]

+Jeff Wallach Not at all. Just be careful removing the case. Easy to snap a coax connector off. Remove the 4 knobs on the scope control and the two knobs on volts/division. Then remove the nuts. There are two thumb screws inside just under the crt. You will see the plate directly under the crt. Once the 2 screws are loose you can them lift the crt and board assemblies out to remove cables.

[@fey4949]

Very nice repair. Cleaning switches is in the top 3 of remedies hi. You see when you move on to the KW 520. Love to see IRF 1200 back working. No need for fancy equipment, it's get the job done. I wish you a good health and til next time. Best 73

[@TheRadioShop]

+FEY Clean switches make everyone happy. I am just glad they designed them to be servable. I think the KW 520 will be my next video. Should be fun. Thanks for the comment and the wish, same back to you my friend..73

[@geckoproductions4128]

Buddy: how about a video on basic IFR 1200 operation and radio troubleshooting? You're a great teacher and I'm sure you'd do a fine job with it.

[@TheRadioShop]

Hi, I am working on doing just that. I am also implementing using it in my repairs explaining how to set it up for a particular task.

[@OrbiterElectronics]

Great repair video Buddy.. Thanks also for the inside tour of that machine.. They don't make'em like that anymore... And by that I mean able to be almost fully disassembled and repaired again and again without bits breaking off etc. Cheers friend John

[@TheRadioShop]

+orbiter8 (John) John you are so right. They are built like a tank. I will say the worse part of the unit is the cabling. So many cables lol. But you know they are like a classic old car in a way. Glad you like the tour and repair of it. Thanks my friend for stopping by.

[@douro20]

They still are. You should see the front panels of the newer instruments; they are machined from solid aluminium, and I know the people who do it.

[@jaybats7865]

I really like your videos and how your knowledge is second to none! Thanks for bringing us along

[@TheRadioShop]

Thank you Jay

[@PapasDino]

Thanks for the IFR tour Buddy. I had the RAM issue on my 1500 a few years ago and simply replacing the battery fixed it like yours. The variable analog attenuator in mine crapped out (noticed it getting flaky while doing a SINAD test one day). Long story short but I ended up having IFR put in the digital attenuator (don't want to say how much that cost, ouch!) so gotta keep my box up and running; hopefully it will outlast me! 73 - Dino KL0S

[@TheRadioShop]

+Dino Papas Hi Dino, good to see you. Man I bet that cost a nice penny. I know just a basic cal was high dollar back in the day. The 1500 is a nice unit.Thanks for watching and sharing that story my friend73

[@raccoonnyc]

You deserve an award just for getting that multi-layer switch out without damage to the board. Even with a good solder sucker and a new tip it can be tricky. Good job!

[@TheRadioShop]

+raccoonnyc Thank you for your kind words. Award eh? he he. Very delicate work. Just coat the entire area in flux, reflow fresh solder, use my 25 year old de-soldering sucker to remove as much as possible, then heat with hot air till the switch falls right off. Made that sound easy huh? Problem is these boards are getting a lot of age on them. Does not take much to rip a trace or via right out. Thanks again my friend and glad you liked it.

[@lindsaykooser5849]

Thank you! I just acquired one of these a couple days ago and had a chance to check it out today. It needed a bit of cleaning and everything seems to be in good shape, It all seems to be working well and your video co0nvinces me that this will be a great piece of equipment. Have you done or considered doing a video run through of the calibration procedures?

[@russwentz3957]

Thank you for your great and kind video IFR 1200 tips!

[@TheRadioShop]

Thanks

[@peternewman958]

Wish I'd seen this when you uploaded it. I could have sent you some of those terminators. I made a 150W dummy load out of one. There good to 100 deg C from memory before they derate!!!, I've got a fan under mine but it's never turned on even running into the load for 5 mins.

[@TheRadioShop]

I still have not repaired this part of It is a 40/10 ohm unit.the unit. Interested in knowing what type of terminator you had at the time. The ones for the IFR are not standard 50 ohm.

[@n0yxl]

I love watching your videos. Very patient and thorough in your explanations and hypothesis. Now, I do have an low mileage and high S/N# 14877 IFR FM/AM 1200S that works great but it always gives off a hot component(s) type of smell while it's been on for a while which is a little unsettling at times. Maybe it's the epoxy in the transformer? It's never given off any magic smoke, but I'm always wondering if it will. Does anyone else with this type of machine have similar experience's? 73, Kyle

[@TheRadioShop]

Thanks for the nice comment. Some of the boards have a bit of varnish on them. And they run hot. I would pull the scope boards and power supply boards and make sure there are no discolored components to be on the safe side.

[@jerrypeal653]

I’ve sure done the pencil method many times , works excellent.

[@cosmocramer1004]

Best repair video in town Thanks

[@TheRadioShop]

Thanks for that very nice comment

[@stevedold4573]

I repaired these for 8 years, probably one to two a week. It was funny how about half of the problems were caused by intermittent wipers on pots, just a small tweak would "fix" the unit. Be careful with those blue boards! I always hated it when I'd open one up and see those.

[@TheRadioShop]

Steve, Thanks for the tip on those blue boards. They are very easy to destroy. I love these old units. Wish I could add a tracking generator to mine. But with the price they want to install I can buy a stand alone unit with more features. Would come in handy for duplexer tuning. Wish more folks would post information on repairing these units. That would really help folks that have set them aside when they quit. But seems those that know are quiet lol.Thanks again for posting. Buddy

[@dennisqwertyuiop]

Great repair, hope it keeps on going

[@TheRadioShop]

+DENNIS N Thanks Dennis. I hope so too. man these are a pain to work on.

[@ebtest7172]

Great video and commentary, and replacing the battery on the CPU board is what I'll be doing very soon, thanks for sharing!

[@TheRadioShop]

Thanks for watching Eric

[@zman4150]

Great video Buddy! My 1200 is showing the "low lock" after a 3 minute warmup, and cycling the power doesn't change it. It's almost like something is changing value as the unit warms up & sends it out of lock. Do you have any suggestions? What was the solution to your issue? It may point me in the direction I need to go with mine. Thanks & 73!

[@TheRadioShop]

If you go to KG electronics you will find the procedure to tune the lock.

[@zman4150]

UPDATE - I had a bad varistor under the shields of the low lock board. I temporarily replaced it with a 4004 diode, and the MV209 is on its way for a proper repair. Any chance you can show us how well (or poor) the receiver is throughout it's spectrum? Or a video on using the 1200 to tune a receiver? Thanks!

[@mikep95133]

Hi Buddy. Same thing just happened to my 1200s yesterday. I had a 120vac ground issue at my work station that I suspect caused it as a radio was not connected to 1200s. Is the internal area in that aluminum box large enough for a 10w or maybe higher power resistors? How deep is it internally using your calibrated eye ? I know that 1200 is out of service now. I'd appreciate your input. -Mike

[@RafałSSS-j5b]

I have a lockup problem when starting ifr1200s. Can you suggest or show low loop adjustments?

[@TRXLab]

Hi Buddy, great video and insights! Bloody expensive spare parts... not nice. That is the problem with our ageing test equipment you can't avoid it really.. Thanks for sharing Buddy all thumps up! 73 my friend..

[@TheRadioShop]

+TRXBench Hi Peter. Always good to see you my friend. Guess our test equipment is getting old like ourselves :" I been looking at buying a third unit. Glad you like the video and thanks for joining in my friend.

[@johncunningham5435]

Fantastic repair; amazing piece of gear that you own and no doubt expensive. But when you consider what it can do, it is well worth the extra cost to bring it back to the original state, "excellent job"

[@TheRadioShop]

+John Cunningham Thanks John. Yes a very nice piece of gear. Just wish I had the tracking gen option. Still need to order the $200 termination pad then it will be complete once again. Although it works just fine as it is. Glad you enjoyed the repair.

[@johncunningham5435]

If the job is not complete you would not be happy. You and I take great pride in our test equipment by maintaining it in like new condition. How many technicians would tackle a wafer switch that are synced so precisely, "not many" they would replace the mechanism if the option were available. That is true craftsmanship.

[@craighold7760]

Thanks for a great video, I so want one of these units.What is your thoughts on using deoxit on the wafer switch contacts?

[@TheRadioShop]

deoxit is great stuff. no problems at all with using it on those. I would apply it with a q-tip to avoid the wafer from soaking up the chemical.

[@mikep95133]

Hi Buddy. Do you think it's possible to use our 1200's as a VNA ? I'd like to test an antenna for resonance.

[@mikep95133]

So much detail! I hope I don't have to go there in the near future. Even great test equipment needs help once in a while. I wonder if there is a way that the 1200s can look at the incoming rf signal and display it on it's own scope or even an external scope? I don't mind buying or making an rf tap, but I would think the 1200s would have it built in? My goal is to monitor the modulated rf carrier on these radios.

[@TheRadioShop]

+mikep95133 Thanks. It is a bit of work if you have to. As far as monitoring the signal plug a cable into tone out or Demod out, then plug into scope in. You can now see the audio component of the signal when you switch it to scope mode. Hope that helps.

[@mikep95133]

+The Radio Shop Is there a way to monitor the rf signal on the 1200s?

[@TheRadioShop]

+mikep95133 Not in the sense that you are thinking about no. As in looking at the raw carrier. It has a audio demodulator built in but the only RF carrier is what you see in the spectrum. I may be wrong, but don't think it is possible with an outside source and using the scopes input.

[@mikep95133]

+The Radio Shop I think you are right. I'll dig up an rf tap when I can. Thanks for all of your time!

[@TheRadioShop]

+mikep95133 Alan w2aew did a nice video on monitoring your ham transmitter with an oscilloscope. Simple circuit you can build and works great. Thanks for the comments.kzbin.info/www/bejne/r2W9pZKCf71kisU

[@Systems-my6ym]

Greetings, I have a Motorola R2600/2660 service monitor, overnight in the spectrum analyzer function it shows vertical lines and the ground level rises to the top of the screen and in the form of points, I don't know if you know what is causing that defect in the equipment

[@stumpor]

t 20:56 you say "Ï will show how to set this in a future video", this being the IFR out of lock. Did you do that video? I have a lock problem and would love to find what you did to fix it.

[@ChrisViningre]

I have a IFR 1200 Super S. When I press 2nd and track I just get an option for duplex hi or low. I want to tune a duplexer but everywhere I look It said to put in track mode. I just got this unit and I don't know if it's working correctly. Do you know any one that I could ask about this?

[@هشامالتميمي-ر2ي]

thanks for the great video, i have a problem that i wish you can tell me how to fix it , the lock led keeps flashing just after i turn it on, and cannot receive any thing from any frequency .

[@TheRadioShop]

Hi, in the service manual it tells you how to set the hi loop and low loop lock unit. One is probably off and needs a bit of adjustment. If that does not take care of the problem then the PLL is unlocked. Follow this link below and see if that takes care of the problem

[@TheRadioShop]

www.kgelectronics.com/kg_electronics_new_beta2p_011.htm

[@wb8cxo]

Hi Buddy, awesome video! I have a 1500 that will need some TLC... Your video gives me hope that I might just be able to tackle the work myself. Definetly will not be spending kilobucks to send it out! I'm wondering if you know any shortcuts on calibration that is another expensive item to have done... I realize as hobbiests we may (and do) get by without periodic calibration but still I'd like to have things as good as I can get it. "IFR Service Monitor Calibration" would a great video to see a brave KZbinr to do! Thanks for your efforts! 73 Mike

[@TheRadioShop]

+wb8cxo Hi Mike. Thanks for your comment. Yes anytime you send one of these out it cost way to much. I agree with your calibration comment as a hobbyist. You are right about a good calibration video being put on KZbin. Perhaps one day I will do that. I will be doing more on this. I do not have a reference stand frequency in my shop. I use WWV as my standard. Cannot get much better than that as a hobbyist. I believe it was Alan w2aew that posted a video on how to set a frequency counter zero beat with WWV. Will have to look that one up again. Thanks again Mile and glad you enjoyed the video.

[@TheRadioShop]

+wb8cxo I just checked. It is Alans video #58kzbin.info/www/bejne/h3StZZaHfLSEgqs

[@rusty1187]

I was able to pick one of these up for under $400. I believe it has a power supply problem. By the way, do you know what the differences are between the 1200, the 1200s, the 1200a, and the 1200 super s?

[@TheRadioShop]

The 1200 is just a plain version with S/A and no tracking gen, the S has tracking gen option. Never seen a 1299a, that one is new to me. The Super S has a bit more memory, different scope/power supply lay out.

[@robertisselhard8957]

1200 had some limited features. 1200S can be upgraded for a tracking generator, not sure about the A,. Super S had tracking generator as standard.

[@DoRC]

ive used pencil erasers for years to clean contacts. they are the best!

[@TheRadioShop]

Agreed!

[@judges69]

Rubber for cleaning switches, wafers, best tip ever.

[@TheRadioShop]

Thanks

[@aaronson2540]

Eraser trick works great cleans it up good... Thanks Buddy another job well done!!

[@beaconmania]

very interesting for me also, my IFR 1500 quitted me years ago. Do you recommend a IFR-based forum where i could fin some paths to begin the repair of this test instrument ? Thans

[@TheRadioShop]

Hi. I wish there was such a forum. Seems those that know do not share information. I sort of have to learn as I go on it.

[@g1fsh]

super video Buddy thank u very much for shateing this information with us. this looks like a very nice test set i have never had one but i have been close to owning one in the past. nice video as allways thank u.

[@TheRadioShop]

+Gary g1fsh Thanks Gary. The IFR series were great units. First one I ever saw is when the owner of the local EF John dealer came out to work on radios in our company trucks. I was impressed with it. I went to work for a GE land mobile radio dealer and we used WaveTek test sets there. After many years I went to work as a service tech for the same EF Johnson guy I mentioned. This is where I fell in love with the IFR stuff. We had a 500 and 1200. We sent the 1200 out for repair and the bill was close to 3 grand. Yikes. Thanks again and glad you enjoyed it.

[@bblod4896]

That is one monster piece of machinery.

[@fltmedic469]

Thanks so much for your time making these awesome videos! I have learned so much on proper sequence of troubleshooting techniques! Once i finally figured out what a "single" was, everything made a lot more since to me haha!

[@TheRadioShop]

Thanks D. I have this bad problem of saying single when I mean signal.

[@wakkowarner7391]

My IFR-1200S has started randomly jittering in output frequency. It can move about 4khz at times even though the lock light is always lit. I'd greatly appreciate any help with it.

[@TheRadioShop]

Open it up with power removed. Pull cables and replace. This helps many times in just reseating the cables.

[@wakkowarner7391]

There's another video showing an IFR doing the very same thing as mine and it turned out to be a varactor diode in the Low Loop Filter. I've got one on order so hopefully that'll solve the problem.

[@willthecat3861]

I've got a 1200 S with the "lock" led flashing. Any suggestions for a fix.

[@RadioRich100]

The scope unit will comes straight up and out if you remove the front panel frame first . 8 screws, comes right off. Far easier than trying to wiggle it out which can scratch the scope window.

[@rcpilot1963]

Thanks for posting.

[@AdemirSoares294]

beautiful service tks!

[@TheRadioShop]

Thanks

[@jimmycake7143]

OK now I SEE why. thanks.

[@biwaUSA]

Great video - really appreciate.

[@paulk8io445]

Thanks, this was very informative!

[@A1CMUGS]

GREAT VIDEO

[@TheRadioShop]

Thank you

[@darylynn621]

I wonder about the cause of the corrosion?What if you found an open trace in the switch? also. if the switch were sealed, would it still be a problem. I think I have one coming in next week, but sure its gonna be a power supply problem,. Never leave a battery in them! Any of them . If you need to run on dc, carry the battery in a sock.Ive seen so much damage from batteries! There is a talk group on Yahoo, if you want to get info. I also wonder if that Resistor can be got from the OEM, much like the Grigsby switch? I snag these type machines If I can for parts when I find them DOA & cheap. My original entry to these was An IFR 1000S, a learning curve that was, I also 'Collect/Conserve ' Cushman CE series Service monitors, as a hobby. 73 de kb5zxm

[@craigrose6249]

Hi i have one of these monitors but it will not generate a signal from the T/R connector no matter where the attenuator is set I measure 50 ohms at the connector Just looking for some advise Thanks Craig

[@TheRadioShop]

Craig, never saw your reply, did you ever get this fixed?

[@craigrose6249]

No never went any further Any help would be great

[@pmkleinp]

Looks like I'm too early to watch this video. Off to bed I go.

[@TheRadioShop]

+Paul Kleinpeter Happy dreams Paul,. It is off to work I go...

[@keithdensmore7766]

Anyone know how to remove the IF Block module from these? Do the circuit boards above it in the cage need removed? Which ones? I have a static voltage failure and need to get at that module. Thanks.

[@robertisselhard8957]

Yes you do have to remove the circuit boards because the screws that hold the IF Block go thru the middle chassis and into the IF Block housing. If you guage from underneath you can tell which ones to remove and how many there are. I watched another tech remove all of them and carefully lay them one on top the other. I would not do that. There are enough cables to replace as it is without making more work for yourself !!! And for anyone interested, the company that made those 40 ohm and 10 ohm termiation resistors for the IFR1200 is no longer in business. And, the location is listed as a "super fund cleanup site" !!! Wow ! Buddy''s replacement idea with the 39 ohm and 10 ohm resistors is a great one. Just to make sure I NEVER have to replace my resistor again (once was enough at $200) I always sink my transmitters into a Heathkit Cantenna and tap off the RCA jack for a small signal output to the IFR.

[@yosemitesamcb930]

Share and share alike!Sharing is caring! Nuff said! Keep up the good work.

[@TheRadioShop]

Thanks, that is what it is all about.

[@carlosdv8291]

Hello Sir…, Can anyone help me contact KG Electronics , if they are still available, I’m possibly needing some parts for my IFR 1200, Thank you Carlo.

[@1233-m4g]

Hello! I am hope for your help. My ifr 1200s does not work. Lamp "Lock" starts blinking after ~5 minutes of operation. In your video you mention this problem, but does not tell how to fix it. 73! RW9UMM

[@TheRadioShop]

Funny but never saw this question. Did you ever get yours repaired?

[@TheRadioShop]

Please do. I like to hear his comments also. And any information he would like to share on the IRF's. Thanks

[@1233-m4g]

I am looking forward to the response. I like my ifr1200. I want to fix it. 73

[@IamDerick]

Another excellent video. Have not broken down and cleaned a selector switch since my Navy days. Do you have a donation button anywhere? Would love to contribute a bit towards the channel to help with production costs and whatnot. 73

[@TheRadioShop]

Thanks. I think you are having a blast watching these videos. I better make more soon or you will run out. This is about all I do is watch KZbin videos. I do not watch TV. Lots of folks are scared to take these apart. But as you know it is simple. As far as donation I accept PayPal if you like to donate. Click the "show more" tab under a video and follow the link labeled "Contact Info". That will take you to my web site. Thanks for watching my friend.

[@IamDerick]

Okay just sent it to your Earthlink account (listed on your website) at PayPal. Cheers!

[@TheRadioShop]

Thank you very much for your donation!

[@jimmycake7143]

Maybe try cleaning those switches in place first?

[@rusty1187]

18:00 How can you pass your amateur radio license test and not know how to repair a radio?

[@scheetz69]

very nice 68 ohio

[@TheRadioShop]

+oHIo VooDoo Thanks friend. Glad you like it. :) Now I have to get busy and upload some more....

[@bblod4896]

Perhaps not, not much room.

[@TheRadioShop]

Yep, not much room in there for anything else.

[@AF6LJSue]

Good Video. :) AF6LJ

[@TheRadioShop]

+S Robins Thanks Sue. And thanks for stopping by. Really appreciate the tip.

[@bblod4896]

Four of these in series? www.newark.com/caddock/mp930-10-0-1/current-sense-resistor-10-ohm/dp/02H2379

[@californiakayaker]

Get one of these, it will help. forums.qrz.com/index.php?threads/help-with-sampler-specifications.622297/

[@TingILi]

What a nice job ... amazing. my one has a receive issue when the frequency is over 350Mhz, the receiver was almost gone, and no waveform coming out. Also, the sensitivity is lower around -100dbm as I test it at the WFM 89~107Mhz band. in fact, I just get it today and so love it, maybe I need your help which gives me some clubs and the techniques to make my ones alive. 😅🥲🥲😁😁