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@@MusicMinisterJP7 just know that the displays are difficult or impossible to obtain. So treat it gently. The modification for full band coverage is mentioned in the video, but email me if it isn’t clear (I’m on QRZ). Other things to watch out for are bad PSU caps (the small ones. The large ones are ok), and bad plastic variable capacitors in the PLL tuners. Fixing the PLL is not trivial and I ended up giving up on my 6M circuits. The entire PLL cavity is filled with wax which you need to remove in order to solder anything. Otherwise though, it’s a fun radio with a lot of built-in functions which just make everything so much easier (PSU, ATU, notch, and so on).

@W6EL I will open it up and inspect inside, for anything odd. I remember you talked about th4 caps. I did like the Japan version with the more colorful display. The one I'm planning to buy just has that orange display, but the swr meter display light wasn't lit. I imagine I can replace it. I did the same on my Super Star s3900G, the light was low yellow. I put an led. Question, is that icon MH12 mic any good, or is there a better mic available for it? Thx. (I didn't catch your email on here)..

@@MusicMinisterJP7 my email address is on qrz dot com. Just log in and then you can easily look it up.

@@W6EL Kool, I signed up.. under JPbravo7.

Any word on the mic?

@@pcfrt Yes, replace the small electrolytic capacitors in the PSU, and it was last a long time. Such a fun radio. 73 from Los Angeles, -E de W6EL

That is odd. Kenwood definitely has some if you call.

So far, the best “cheat code” I know is to tap “VOL” to get out of any waiting period. That’s your “exit” button basically. Yes, I do have the head unit open. It’s not too hard to take apart. Mine is actually quite clean inside. Well-sealed. The thing is also very modular; you can pull the boards from each other pretty easily. Don’t forget to take ESD precautions, many of these chips are unobtainable. I’ll have a video about it when I get to editing it. 73

@@W6EL Yes the VOL cheat code is a go to. oh man it was much simpler of a fix. I got really lucky! Turns out the wires from the head unit were not solidly connected to the screw in terminal block. So after reconnecting those it worked just fine! I have been having a blast with this radio! My furthest voice contact so far is Kuwait from Maryland. I also used it portable on a recent Maryland QSO party. I ended up getting 60 contacts while operating out of there different counties. I have not put the radio on a power meter. I have been trusting what it has been telling me, the SWR levels have been close to what my analyzer said. Also I am curious if you have thought anymore about connecting to the serial port that it has for CAT control? My initial thought are an AIOC or Digirig as they both can enumerate a serial port and sound card when plugged into a computer. Then you could get serial command but also tx and rx audio to the computer. The other thought I had was an ESP32-S3 have that wire interfaced with the radio and then communicate with it over WiFi. The latter seems like a heavier lift and I am not sure the ESP33s ADC are high enough resolution. The former I think would be almost plug and play after some wire making

Sadly they are gone.

@@charleswalker4959 about $200. Maybe $250 if tested and good condition.

@@melissarainchild Hi, unfortunately the 897 does not speak Icom CI-V, nor does it provide the spectrum data (if it does, please let me know and maybe we will eventually add it). 73!

@@W6EL Thank you very much. Best of luck with this great tool...73's!

Very good. How many current 100 MHz scopes can be pushed to 400 MHz though...?

@@pauliedweasel even my ancient IC-736, from Icom, has band and frequency combo buttons. I really don’t understand how they allowed the interface of their flagship radio to regress like this. That said, it’s still a great radio in so many aspects.

You just made my day! I’m glad you’re enjoying it. Keep your eyes peeled for version 2 (you can install it and preview it under Linux using our build script with “creator-widgets” as the argument). 73 and thanks!!!

@@W6EL excellent! I'll be glad to try it. I've read that other hams are having good luck with connecting through wfview via WiFi and leaving the serial connection for other apps. I am going to make that a mission before the grill fires up today!

I guess that is how class A amplifiers work! Most of my hf experience has been in the QRP world with a class E power amplifier.

Yes, 100%. That’s the only way to match the impedance from source to load. If it’s matched, power dissipation is equal. You can prove this to yourself with ohms law and a circuit with two 50 ohm resistors.

Class A is a bit more difficult since there is presumably a single device required to be on the entire time. There is essentially power wasted when you do this, but the upside of course is that the device is always on and thus always biased in a linear region.

I try! I wish I knew what to attribute these issues to. I feel like a lot of it must be basically part of the design, but perhaps it was made worse with age and/or exposure to the marine environment. If I had a second radio to compare with that would really have been fantastic. I was honestly not sure what to expect. The strong harmonic filters on HF radios are clearly there for a reason, but what I don't have is a baseline as to how much harmonic is "nominal" prior to those filters. I wish I had taken more images with the scope. 73 and enjoy.

@@W6EL so hypothetically speaking, if I did get one and it were to show up on your door step, would you be interested in trading the experience of having a second one to compare to for giving the second one a once over(just a diagnostic not any repairs) and then sending it back to me I would pay postage both ways. I don’t have the know how or the tools to really trouble shoot issues if there are any. Well your video series on this radio is a tool that I have. Something I could contribute to, maybe would be trying to integrate this radio to the wfview application. Thank you for making that open source! You obviously know this radio and wfview do you think that is a feasible integration?

I am more comfortable in the software world than the hardware world

@@nehem11e I would love to do a comparison, but I'm afraid I would never get around to it! I have so many radios and projects lined up, plus work, family, and more. It might be smart for you to get some basic equipment and just see if you can give it a once-over to see if it's producing power and receiving reasonably. Gosh it would be fun though. If there were a bit more time in each day I'd go for it! As for wfview, with the commands for the SGC given in the manual, it seems like something that could be done. We would need to ADC the S-Meter and possibly add PTT from some GPIO pins. It could get a bit messy. But the radio has enough commands otherwise, and they clearly were ahead of their time with the RS-232 port and the commands given out. The next version of wfview features much more radio abstraction as well as a tool to create radio interfaces. We will be looking at supporting other radios, even radios with wildly different commands. I suppose the SGC would be even more exciting with an SDR tap!

@@W6EL so you sound like someone who might be interested in my Time Machine! It’s similar to a bread machine in that it makes time. It doesn’t travel through time. Need an hour here you go. Unfortunately I haven’t had time to build the machine yet….. I totally understand the full plate, maybe not totally, I don’t know how you RUclipsrs do it all and video record it(re-record, post process,etc). I have tried to make some videos to share ideas but man that makes the task so much longer. So thank you for taking the extra time to share what you do!!!! I will definitely do some preliminary testing with what I have and I can reach out to the clubs I am in for more equipment or help. I guess at this point it is all hypothetical I haven’t gotten the radio yet.

Around $250 is a good price. Not worth over $350

You’re right, but I think you’re missing the point. My analog scope is ancient too. So here we have two old scopes. The digital one is a good bit more modern but they are both quite old. I use very fancy and sophisticated scopes at work all the time, but they cost more than a mortgage… if someone wants to make a rebuttal using *affordable* modern digital scopes I would honestly enjoy it and I hope someone does.

I think it would be a great POTA radio too. I often run HF mobile, and I’d appreciate the extra couple dB! There are two or three TR relays, I’d start there. Also check the transmit switched 13V by reading the bias voltage on those jumpers on the power board. Check the fuses while you’re there. Email me any time with questions. Let’s get these radios rockin’!

We’ll get there man! I will definitely be addressing the dumpy audio (they all have this issue) and yeah I do want to fix my FWD/SWR metering. It always shows about “2”. Maybe the diodes went bad? We will see. Maybe I’ll start by just injecting some DC to see if it reads correctly. These are neat radios, I hope we can keep them on the air!

@@W6EL I have had my 2000 apart many times, so I can follow along. A basic question. How did you determine the relays were faulty, with high resistance? My unit also has trouble hearing signals my other radios hear. And it's not putting out enough power on SSB, though it shows a full 150 watts on CW.

@@valdemarphoenix2685 for the receiver, the relays pretty much are the only thing in this radio that is changing per band. I proved it was the relays by disconnecting the receiver feed from the LPA board and running low level RF through the LPA board, fed from the normal coax jack and coming out the wire that normally feeds the receiver on the “exciter/main board”. With that setup I saw significantly less signal on some bands (as you see in the video). But I also did a simple test with a DMM, measuring the ohms through the LPF. That was a bit tricky but I found spots I could probe eventually. You must disconnect the receiver if you do this and use a volt meter with a low compliance voltage, just to be sure. I also think the two zener diodes in the forward and SWR metering area are dead. Mine do not measure correctly in-situ. Additionally there are some capacitors around the MRF-455 transistors which I am investigating. I will post more for sure.

@@valdemarphoenix2685 I just found D17 and D18 were bad. These are in the forward and reverse power metering circuits. Easy to replace. 1N4148. You can use your DMM in circuit and see what the reverse voltage is. Mine was 0.6 forward and 3 volts reverse. Should be 100 volts reverse (unable to read is normal with a 4148). Hopefully this will fix the metering in yours. I have not verified it here yet as my radio is still in its natural habitat - open and on the bench.

@@W6EL Thanks very much for your very detailed reply. I'm not an engineer; just a very casual amateur. I do have a digital multimeter, so I can do some of those tests. I don't have the very impressive set of tech equipment you have. But it all makes sense as you explain it. I'll do what I can with what I've got. LOL.

Good question! I actually keep the modulation off on the HP. It's just generating a carrier (it says FM MOD but the mod is off). That is why I tune to 14.999 on the SGC. This places the carrier of the HP 1 KHz in to the passband of the sideband demodulator on the radio, and thus a 1 KHz tone results. This is the most "pure" method of doing it and also results in the fewest of calculations. I probably should have mentioned this in the video; I may make a video specific to sensitivity testing soon (one for FM, one for SSB). 73!

@@W6EL AM too Please? :)

Certainly. Basically the generator with AM MOD turned on, tuned in exactly on the same frequency, followed by the same procedure.

@@W6EL What Modulation Depth would be good?

@@dragonlard4595 30% is commonly used. It makes a great deal of difference how you set these things up, filled with subtlety. I liked this video on the topic: ruclips.net/video/F9CAj3atqEk/видео.htmlsi=NfVuSbfcXoq92Oe9

I figure, if I’m going to take something apart and look around inside, I may as well share the journey. It’s too much fun to keep to myself!

My RX audio in the head is also kinda iffy. I will definitely pull mine apart and make a video. Hopefully we can improve things. I think new caps are a reasonable start. I’m also going to lower the gain on the final audio amplifier. I think that’s part of why it sounds so awful. Yours sounds ok if you tap into the rear audio output (aux/telex) port?

@@W6EL I will check that out and let you know. Thanks for your input.

@@kevinmccool3719 no problem. I’m looking forward to tackling the head unit. I’ll probably do the relays first though. Just to get it half way working.

Never mind I found it!

@@richardgreaker2522if you are successful let me know! I am still working out what to change in the LPF.

I have about six rolls here.

Thank you! The end result was definitely worth it.

Nope. Only some of the MKIIG units.

As mine has gotten more wobbly over time, I agree. My “MULTI” encoder knob also skips spots sometimes. All my other Icom radios feel much better. Not sure what happened here with the component selection process.

Oh wow those are definitely some neat radios. I am sure they will do a fine job on the air. Maybe add a digital VFO externally so that you can tune around? I wouldn’t put it in the same chassis since it is definitely not “original” in any sense. Thanks for your comment, I appreciate it. It’s fun to mod things and learn about them. 73!

I believe that would be the Brother 5250DN. Any printer that supports generic postscript should be ok.

@@W6EL Thank you !

I’m still trying to “know” why I’d want four S-meters or why I’d not want to be able to edit memories! 73!

Got mine on eBay. There is a seller in Florida that seems to part radios out.

Thank you sir for your help

Make sure you actually need this bias resistor mod first (check the gate voltage per the video). Yes, I would do the fan mod (mine has it as you see). Also check the electrolytic caps for any signs of leakage while you’re in there. 73!

@@W6ELI checked the voltage on my 706 MKIIG and it didn’t show a mV. I put it on USB and LSB, but it didn’t read anything close to 1v. It was like 0.2mV. I could be doing something wrong. I set my meter to DC Auto and then to V and mV. Should I be seeing that?

@@hillbillytarzanDid you make sure to transmit during the test?

@@W6ELno. I misunderstood what you said in the video. I was thinking you read the voltage while sitting idle in rx mode on SSB. So I test with the mic keyed with no modulation? If I try enough times, I'll get it right sooner or later 😂

@@hillbillytarzan the idea is to key it up in sideband but without any modulation. You can see the mic gain to zero to make sure (don’t forget to crank it up later). Then measure the circuit’s DC voltage. See if it’s around 2-2.5 volts (good) or as bad as 4 volts.

Is the decay time adjustable?

@@W6EL No. Just the brightness. But it acts like an analog scope. I use mine for video on adjusting laser eye patterns when I fix CD players. It does a fine job emulating CRT's. It's also faster and has FFT math built in. The other advantage is that it uses a normal battery for cal backup instead of a Dallas chip.

@@Runco990 that last advantage, with the battery, is a good one for sure. Does the FFT require an added module? I see there is also a 4ch version…. Hmm!

@@W6EL FFT and asteroids game are built in. I have the 2 and 4 channel version. You can also get a 350Mhxz (I have) and a 500Mhz version. I do have a Rigol 2000 series scope, but I put it in the closet. The HP is just a nicer bench scope AND you can actually SEE the readouts on the screen, unlike the Rigol which was likely coded by teens with iPhones and 20/15 eyesight.

​@@W6ELpretty much any modern dso has some kind of FFT built in, even the chinese ones, of course it isnt as good as a dedicated spectrum analyzer but pretty decent.