Re: TX / RX Frequency Alignment
Thank you for this information, Mat. I dont know that until yet. Very good to know !!
vy73 de DL23EBZ, Bodo
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Re: TX / RX Frequency Alignment
Hi DL2EBZ,
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There is certainly a very limited range on the "stock" variable pulling capacitor in the oscillator circuit.
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If you run out of range, you can add or remove capacitance by changing values of the fixed parallel capacitors. Be sure to use high quality NG0/C0G capacitors if you do this. This can allow you to continue to "calibrate" your rig without replacing the crystal.
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-Mat Breton, N8TW
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Re: TX / RX Frequency Alignment
Hi Brian,
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There is nice article on the thermally-stabilized crystal in the Files section (how it works, how to adjust): See below:
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Hope this helps,
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-Mat Breton, N8TW
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Re: TX / RX Frequency Alignment
Hey Brian.
Last year I gave my '980' to a complete service - a complte check-up. It needed about 6 month and costs about 850,- �. One of the points to make better, was
the bit of frequencies-difference. Not much difference - but even not exact. What the repair-shop tells me:? the reason is the 50years old xtal. You can adjust a little bit - but not enough as
it needed.?If you can get a new xtal - and it means 'a very new'?x-tal, you can change it. But it's not easy - and perhaps it is not necessary for this little difference.
That's what I can tell you what a specialist have told me last year.
Perhaps it helps.
vy73 de DL2EBZ??
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Re: TX / RX Frequency Alignment
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On Feb 23, 2025, at 10:13?AM, IN3FTD via groups.io <in3ftd@...> wrote:
? Hi,
?? on the right side of the cabinet (facing at the front panel) there is an access hole to TC7001, located in the VFO unit.
With a plastic screwdriver you can adjust this trimmer capacitor against a RX signal coming from a frequency standard station... it's a very easy procedure that can be accomplished without removing any cover.
With the rig tuned at the same frequency offset respect the carrier frequency, you should receive the reference signal with the same audio pitch either in LSB and USB mode. Obviously make sure that the shift/width knob is properly centered before adjusting TC7001.
I also had my rig about 300Hz out of frequency and now is centered again.
In website you can download the FT-980 technical manual where you can go in depth of any maintenance and adjustment procedure.
Here TC7001 is adjusted by means of a frequency counter connected to the given test point. But if you don't have a counter or you don't want to disassemble the rig, this is the easy way that works as well.
73, Francesco IN3FTD
Ottieni
Il giorno 23 Feb 2025, alle ore 16:18, "Brian Harris via " < yahoo.com@groups.io target=_blank> [email protected]> ha scritto:
I am fairly sure my actual receive and transmit frequencies are off a bit. Are there simple adjustments to correct? My transceiver is untouched from new except for a batter replacement.
Brian WA5UEK
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Re: TX / RX Frequency Alignment
Hi,
?? on the right side of the cabinet (facing at the front panel) there is an access hole to TC7001, located in the VFO unit.
With a plastic screwdriver you can adjust this trimmer capacitor against a RX signal coming from a frequency standard station... it's a very easy procedure that can be accomplished without removing any cover.
With the rig tuned at the same frequency offset respect the carrier frequency, you should receive the reference signal with the same audio pitch either in LSB and USB mode. Obviously make sure that the shift/width knob is properly centered before adjusting TC7001.
I also had my rig about 300Hz out of frequency and now is centered again.
In website you can download the FT-980 technical manual where you can go in depth of any maintenance and adjustment procedure.
Here TC7001 is adjusted by means of a frequency counter connected to the given test point. But if you don't have a counter or you don't want to disassemble the rig, this is the easy way that works as well.
73, Francesco IN3FTD
Ottieni
I am fairly sure my actual receive and transmit frequencies are off a bit. Are there simple adjustments to correct? My transceiver is untouched from new except for a batter replacement.
Brian WA5UEK
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TX / RX Frequency Alignment
I am fairly sure my actual receive and transmit frequencies are off a bit. Are there simple adjustments to correct? My transceiver is untouched from new except for a batter replacement.
Brian WA5UEK
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Re: kp keypad tone non functioning
Thinking further: was there any chance that the keypads were swapped?
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I am wondering if one of the piezos could have shorted to ground and taken out Q6015 (the driver transistor). If swapped, it would have taken out the other driver transistor in the other rig.
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Just a thoght,
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-Mat Breton, N8TW
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Re: kp keypad tone non functioning
Hi Robert!
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I've never liked the keypad beeper on the FT-980. Mine is VERY quiet and quite high-pitched. During normal operation I can't really hear it over the normal HF hiss. Since there is no "side-tone" in the audio path, if you are wearing headphones it might as well not exist. Additionally, there is no volume control for it that I am aware of.
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So, that being said, let's dive in. For whatever reason Yaesu decided to implement a small piezo buzzer from Panasonic (an EFB-R series buzzer) right on the keypad. Now, there is a perfectly good audio path they could have injected it into, where we could have put volume control, heard it over an external speaker/headphones, etc. But, whatever ...
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The exact part was the Panasonic EFB·RE25D02, which is an EFB-R series, external drive (I believe), 2.5kHz resonant, small diameter piezo. These are typically fed by a 15Vp-p square wave. From the schematics, it appears that Yaesu might have used a 5V square-wave.
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From the symptoms it sounds like the piezo element in your buzzers is loose or broken. Odd this occurred in the same time period, but ... who knows.
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Although this buzzer does not appear to have been produced in some time, there are numerous ones that are very similar in specs/performance. You might want to check/compare the TDK PS14 series parts. These are < $1 at Digikey in quantities of 1.??
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The one thing I am not 100% sure is if the buzzer is internal or external drive. It "looks" external ... but without ripping my unit open I can't be sure.
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-Mat Breton, N8TW
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kp keypad tone non functioning
both my 980s been sitting around unused for many years. now neither of rigs, the kb buzzer non functional. worked the rear kb switch many times- no change.
need to get to the keyboard where buzzer located and tap in it while energized. ?anything am i missing here
tnx
bob donchez
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Re: need a power on off switch
The listed shipping on that item is over $100 USD. From Oklahoma? I think there is a typo in his shipping details.
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Looks like he parted out an FT-980: lots of parts listed in his ebay "store". The others all seem to have reasonable S&H charges.?
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-Mat Breton, N8TW
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Re: need a power on off switch
Hi Bob, if worse comes to worse, looks like there is one available for sale on Ebay right now:
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Mike - KQ4VKJ
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need a power on off switch
a friend has just brought back my 2 - 980s- bought one year after another in 82/83- even cleaned all switches, connectors, bench tested all at length- the power switch arced bad and pops loudly when used- so he jumped it out and been using power cord on and off
just thought id ask if anyone might have a parts radio that could spare a switch
tnx
bob donchez
610-833-2966
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Hello everyone? ? ??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? ? ? ?? ???????????????????????????????? My wife's ft 980 has had the same symptoms for some time. This weekend I took the time to thoroughly investigate the problem (replacing the 2 AA backup batteries did not bring a solution) and try to solve it. I started by disassembling the VFO knob with the 2 optocoplers PCBs (pull out plug J1301 on the dial unit). The error was in 1 of the 2 pots (10K), I replaced both pots as a precaution. For soldering set to about 2.7K The dial worked perfectly directly again after assembly, turning clockwise only resulted in a reduction of the frequency and anti-clockwise turning resulted in an increase in frequency. I don't know why this phenomenon occurred because only the pots have been replaced. As a solution, I just swapped pin 2 and pin 3 of the J1301 plug. Works perfectly now!?????????????????????????????????????????? 73 Andre? ON4DTO
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Re: Garbled Voice USB and LSB - troubleshooting and repair advice
There is nothing complicated, we throw away the generator on the quartz, and instead we put TCXO 30,000,000 mHz
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Re: Garbled Voice USB and LSB - troubleshooting and repair advice
Ur9ip,
Sounds very stable / accurate and a nice upgrade.?
Was it very expensive?? I wasn't finding anything with that spec PPM out on digikey.? Do you have a link to where you were able to buy it?
How much trouble did it take to install it?
Thanks,
Mike Nicholas, KQ4VKJ
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Re: Garbled Voice USB and LSB - troubleshooting and repair advice
Hi, I struggled with the 30 MHz generator for a long time, then I installed TCXO 30,000 MHz 0.01 PPM, and forgot about the problem
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Re: Garbled Voice USB and LSB - troubleshooting and repair advice
You are very welcome, Mike. Glad we were able to help!
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Just a note: it is possible, even likely, that the trim capacitor will continue to drift. You might need to repeat this someday ... or possibly even to replace it if at some point it drifts to where you won't be able to find a stable setting.
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P.S. Welcome to the group. There is a LOT of information on the radio in the Files section.
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-Mat Breton, N8TW
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Re: Garbled Voice USB and LSB - troubleshooting and repair advice
Wow!? I went through checking the BFO value SHIFT setting voltages as you suggested and they were indeed *way off*.?
Once I was able to get them back adjusted to the proper voltages, all seemed to fall into place and everything started working and the USB/LSB voices cleaned right up.? Also, now when checking, I pulled in a ton of CW on the lower 40m and it is much cleaner than before.? I'm thinking the CW modes were also affected but just had nothing to compare to.?
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Thank you so much for your help Mat with this,? I do appreciate it!
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Best,
Mike Nicholas, KQ4VKJ
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Mat Breton N8TW
Ur9ip