Re: FT-980 Performance Measurments: Sherwood Engineering
?I changed the 2,7kHz 455KHz Murata for a 455kHz 2,1kHz Inrad. Now the radio is 250gr heavier and the Width control works properly. In pair with a couple of modern digital rigs
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Re: Is this a factory mod?
3D 010641 is not a late model, it is number 0641 of the 01 series. One of the first radios produced. The 3D refers to dates. It is in the service manual.
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Hi Fred,
I have a bit of luxury regarding time, most of the restoration projects that I have done have involved a complete strip down, often a sand blast of the chassis followed by a replating and sometimes even a polish, then the slow rebuild of each component as well go, with all other metalwork such as VFO's and Inductors, etc spending multiple times in the Ultrasonic cleaner till I am happy with them. with all that and the hunt for parts that often take much longer than I would wish, but it does mean that I will try my best to find each missing part as I go, I have restoration projects here that are still going after 15 years, most seem to take about 10, but when finished I more often that not will end up with a new st that will look a lot nicer than when it was first built.
So I am happy to wait till I can find the exact part that I need. Anyway this FT-980 is also being totally re-wired, a lot of the horrible 'Yellow' wires that fly all over the chassis in this one that I have are in such as state that when you touch them or move them the coating starts to crack or just breaks off in large lumps, so each PCB and attached hardware is slowly removed and catalogued before being cleaned and tested.
It's a slow process, but like most old radios as it takes 'SOOOOO' long to find old parts I can afford to wait, Thanks for the ideas, I have done similar in the past, but this was never meant to be such a big project, I much prefer slightly older Vacuum based kit like the Drake and KW Electronics kit and even early kit from the 70's and 80's. This old 980 has now turned out to a really monster job, I am going to need quite a few old parts from donor radios to get this working sweet again.?
Kind Regards
James
MD0MDI
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There are two styles of that knob which I've encountered. One is the splined - used on our FT-980s. The other is flatted - and this is seen on other Yaesu models such as the FT-757/FC-757.
What I would consider is finding a length of 6mm diameter aluminum shaft that you can contour and groove so it approximates the OEM splined part. Then, machine a flat on the panel end to allow a 757-series selector knob to be used. Sets of these knobs come up somewhat frequently on the auction site.
Keep the splined shaft for future use or sell it to someone whose rig was damaged in shipping, as they sometimes get broken as the result of a clueless packing job.
73 - Fred, N8YX
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Awesome, Matt,
Just like mine, that has put my mind at rest, I just need to keep trying to locate this knob to at least complete the front panel, as well as the ever growing list.
James
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  -- -Mat Breton, N8TW
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Re: Untunable SSB, CW. but AM is OK
I seem to recall the voltage should be 6.3v on both Upper and lower SSB.? This may have come from a 1983 FOX Tango newsletter but it may also be in the FT980 tech supplement.? If you don't have the tech supplement I suggest you get one.? Has alignment procedures and a whole set of schematics.? They sell on RBAY often.
Dave K4JRB
-----Original Message----- From: < [email protected]> Sent: Oct 9, 2022 8:25 PM To: < [email protected]> Subject: Re: [Yaesu-FT-980] Untunable SSB, CW. but AM is OK
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[Edited Message Follows]
You can check if the BFO oscillator (the one in the tin can) is working by checking the DC voltage on test point TP4004, which is actually located outside of the tin can (not the one inside). The test and adjustment procedure is located on page 23 of the Technical Supplement. It takes a very steady hand and good tools to adjust the stock trimmer (peak the voltage on TP4004). Note that the exact voltage levels can vary rig-to-rig, but you should see 2-7 volts at all times, and there should be a 3v or so movement as you sweep the width knob. -- -Mat Breton, N8TW
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Cheers for that Matt, it is just that I have bought off eBay 3 complete sets of knobs suposably for the 980 but the knob that should be on the ATT are all D shaped, thus I was thinking it had been changed at some point, I will just have to kep buying sets till the right ATT Knob comes along.
Thanks for the help, it is very much appreciated.
James
MD0MDI
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Re: Untunable SSB, CW. but AM is OK
Thanks for your posts Mat - very useful. I can "hear" SSB and CW but very muffled and indistinct. I did check the master oscillator (30MHz) and this was a few KHz low so that was corrected. But I couldn't find the 90MHz signal after the tripler! Maybe I should check these oscillators then proceed to the BFO.
Very grateful foir your help Mat
Peter G0LQU
Mat Breton N8TW wrote:
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Show quoted text
[Edited Message Follows]
You can check if the BFO oscillator (the one in the tin can) is working by checking the DC voltage on test point TP4004, which is actually located outside of the tin can (not the one inside). The test and adjustment procedure is located on page 23 of the Technical Supplement. It takes a very steady hand and good tools to adjust the stock trimmer (peak the voltage on TP4004).
Note that the exact voltage levels can vary rig-to-rig, but you should see 2-7 volts at all times, and there should be a 3v or so movement as you sweep the width knob.
--
-Mat Breton, N8TW
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The shaft is round (not a D-shaft), splined, with a single split. The split is not used by the knob ... but the splines are.
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-Mat Breton, N8TW
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Thanks for the info but that is not really what I am after...
I just want to know if you remove the knob from the ATT switch is the shaft round or does it have milled shaft, i.e. the shaft will be mostly round with a flat side to enable the knob to be screwed and thus locked in place.
Thanks?
James
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I don't have mine open at the time, so I am going from memory and the docs. It is actually a double-pole quad-throw (DP4T) switch.
The MPN is?SBU2044N(10)-R15, but I can't find any information online on it.
That is all I got w/o cracking my unit open. I've had the shaft out when working on the RF board, but I can't recall the mechanical details.
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-Mat Breton, N8TW
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Re: Untunable SSB, CW. but AM is OK
You can check if the BFO oscillator (the one in the tin can) is working by checking the DC voltage on test point TP4004, which is actually located outside of the tin can (not the one inside). The test and adjustment procedure is located on page 23 of the Technical Supplement. It takes a very steady hand and good tools to adjust the stock trimmer (peak the voltage on TP4004).
Note that the exact voltage levels can vary rig-to-rig, but you should see 2-7 volts at all times, and there should be a 3v or so movement as you sweep the width knob.
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-Mat Breton, N8TW
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Re: Untunable SSB, CW. but AM is OK
Can you hear CW? If CW/SSB both do not work, but both AM/FM do then it lends itself to a BFO path problem (oscillators, amp, or mixer). You can check FM station by switching to GEN mode and listening into a maritime mobile or broadcast segment.
There is a good oscillator block diagram on page 49 of the FT-980 Technical Supplement ... but I usually use the big block diagram as the oscillator one over-simplifies things.
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-Mat Breton, N8TW
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Re: Untunable SSB, CW. but AM is OK
Thank you so much Mal for that information and the pictures.and the offer of a variable Cap if I need one. I've just managed to get off the main metal lid of the VCO/PLL unit and am now confronted by that little metal box you mentioned. I may try to adjust the cap through the holes in the box, although the alignment is not great for accessing the adjusting screw head! One hole givese access to a test point so I will look that up.and see if I can measure anything at that point.
My "solder sucker" iron is not strong enough to tackle the metal lid solder so not sure how to proceed yet with that.
Kind regards
Peter G0LQU
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Hi Guys, I am having a problem locking a knob for my FT-980 restoration, mainly due to the shape of thew shaft.
Can anyone please let me know if your ATT pot is either all round, or does it have a flat?
Mine has a round shaft, and it does look as though it is original, the soldiering and the wiring looks to be untouched, but saying that, this transceiver has been heavily played with and I am in the middle of replacing all of the internal wiring, and trying to work out what has been changed in this radio, there are many extra wires that are clearly a bodge by someone, and you can see that who ever did these modifications was a terrible solderer.
If anyone can help it would be very much appreciated as I am unsure if I need to replace this pot, as I cannot get a ATT Knob anywhere that fits onto a round shaft.
Kind Regards
James
MD0MDI
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Re: Untunable SSB, CW. but AM is OK
Hi Dave and many thanks for your (ground breaking for me!) information. Yes my FT 290 IS a very early model. G0MIX has also confirmed this with me and sent useful pics of the location of that cap.
Kind regards
Peter G0LQU
Dave Thompson wrote:
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Show quoted text
Sounds like the small variable cap in the VCV. Use a non metal adjustment tool and see if you can get the audio working. First test LSB and compare to USB.
If there is a big differece then the VCV cap needs to be adjusted. This was a major problem in early FT-980's. My first was bought new in 1983 and later models have a better ceramic variable cap. Everything else looks OK. Good luck.
73 Dave K4JRB
-----Original Message-----
From: <[email protected]>
Sent: Oct 7, 2022 1:35 PM
To: <[email protected]>
Subject: [Yaesu-FT-980] Untunable SSB, CW. but AM is OK
By fiddling with the I.F. width control I can "almost" resolve speeech on SSB but clearly something is wrong, with my money on a drifted oscillator.
I did check the Master Oscillator (30 MHz) and this was slightly low so I corrected this. I then checked the tripler output for 90MHz and it wasn't there - but 30 MHz was!
I thought maybe the 30MHz was bleeding through a weak 90 MHz but cant check this at the mo. as my 100MHz scope has packed up.
I read Mat's description of his similar fault and cure but was not sure of the location/part number of the trimmer cap he mentioned and ultimately replaced. I did locate the transformer he replaced but I havn't check mine yet.
So my question is (mainly for Mat?) "Can you state where I can find that variable cap you replaced? You mention "two tin cans" and I wondered if this was in the VCO enclosure (how do you get the lid off?!!) or is it on the VFO board. Can't quite place you photo.
Kind regards
Peter G0LQU
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Re: Untunable SSB, CW. but AM is OK
Sounds like the small variable cap in the VCV.? Use a non metal adjustment tool and see if you can get the audio working.? First test LSB and compare to USB.
If there is a big differece then the VCV cap needs to be adjusted.? This was a major problem in early FT-980's.? My first was bought new in 1983 and later models have a better ceramic variable cap.? Everything else looks OK.? Good luck.
73 Dave K4JRB?
-----Original Message----- From: < [email protected]> Sent: Oct 7, 2022 1:35 PM To: < [email protected]> Subject: [Yaesu-FT-980] Untunable SSB, CW. but AM is OK
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By fiddling with the I.F. width control I can "almost" resolve speeech on SSB but clearly something is wrong, with my money on a drifted oscillator. I did check the Master Oscillator (30 MHz) and this was slightly low so I corrected this. I then checked the tripler output for 90MHz and it wasn't there - but 30 MHz was! I thought maybe the 30MHz was bleeding through a weak 90 MHz but cant check this at the mo. as my 100MHz scope has packed up. I read Mat's description of his similar fault and cure but was not sure of the location/part number of the trimmer cap he mentioned and ultimately replaced. I did locate the transformer he replaced but I havn't check mine yet. So my question is (mainly for Mat?) "Can you state where I can find that variable cap you replaced? You mention "two tin cans" and I wondered if this was in the VCO enclosure (how do you get the lid off?!!) or is it on the VFO board. Can't quite place you photo. Kind regards Peter G0LQU
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Re: Untunable SSB, CW. but AM is OK
Hi Peter
I had similar problems with my ft980 and replacing the trimmer capacitor you mention and worked for me its located on the VCO/PLL board part number TC4001 its a? 1-3pf its inside a metal enclosure you will have to carefully remove the lid by unsoldering the tags ether side,? a replacement trimmer is not easy to find, but I do have one here if you have trouble? getting hold of one just e-mail me my info is good on QRZ.co   Cheers Mal G0MIX?
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Untunable SSB, CW. but AM is OK
By fiddling with the I.F. width control I can "almost" resolve speeech on SSB but clearly something is wrong, with my money on a drifted oscillator.
I did check the Master Oscillator (30 MHz) and this was slightly low so I corrected this. I then checked the tripler output for 90MHz and it wasn't there - but 30 MHz was!
I thought maybe the 30MHz was bleeding through a weak 90 MHz but cant check this at the mo. as my 100MHz scope has packed up.
I read Mat's description of his similar fault and cure but was not sure of the location/part number of the trimmer cap he mentioned and ultimately replaced. I did locate the transformer he replaced but I havn't check mine yet.
So my question is (mainly for Mat?) "Can you state where I can find that variable cap you replaced? You mention "two tin cans" and I wondered if this was in the VCO enclosure (how do you get the lid off?!!) or is it on the VFO board. Can't quite place you photo.
Kind regards
Peter G0LQU
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James Sawle (MD0MDI)
Mat Breton N8TW
Mal Jones G0MIX