Thanks for sharing, a good troubleshoot and restoration. I see the ICs are from 1981, so the radio lives on. An accolade to Japanese build quality and engineering
Hi Graham, great looking radio my friend! Excellent assessment of the problem with the band selector, looking forward to the next instalment. 73! Clint
I wonder if the issue could be the result of irregular behaviour in the PSU, I experienced frequency issues (locked VFO) from a dry solder joint on a regulator on the power supply board of the R1000 which supposedly uses a similar circuit design to the FRG7700.
Good call Dave. One of the jobs that's a must is to recap the power board and fit a new regulator. All on order so should be here tomorrow. Thanks for the help and please let me know if you think of anything else. Graham
I just sall all your videos related to repair of this radio congrats a lot of great work you have put here. i got recently one as well and look like to have one issue frecvency nob is moving with some rezistence i could say and even if calibrate the frecvency for example on 1 MHZ calibrate (the electronic display with the dial) and by 2 Mhz already have discrepancy any suggestions? Thank you in advance!
It will certainly be interesting. I've worked on a few older ham radios in the past and did have one of these for a short while but traded it for a JRC NRD-535. Got to find a frequency counter now
+Radiocruncher You could use the oscillator field of another receiver to generate an injection signal if you get stuck, though that generally is only of use for dial alignment :)
Thanks Dave. From initial finding the dial alignment is pretty much there. I did compare it with my Icom IC-7800 to verify the 20m band but haven't gone through all the bands yet
Seems that it might be possible Simon. These have a reputation of the power supply failing. I ordered all the caps and a replacement bridge rectifier earlier so should be here tomorrow. You ever had one of these in?
Thanks for sharing, a good troubleshoot and restoration. I see the ICs are from 1981, so the radio lives on. An accolade to Japanese build quality and engineering
Thanks Jon. It certainly gave me the runaround. It should last many more years to come
Hi Graham, great looking radio my friend! Excellent assessment of the problem with the band selector, looking forward to the next instalment. 73! Clint
It's a strange one Clint as it appears to right itself after a while. Hoping its just a dirty switch. 73 Graham
Yes, let's hope so! 73! Clint
I wonder if the issue could be the result of irregular behaviour in the PSU, I experienced frequency issues (locked VFO) from a dry solder joint on a regulator on the power supply board of the R1000 which supposedly uses a similar circuit design to the FRG7700.
Good call Dave. One of the jobs that's a must is to recap the power board and fit a new regulator. All on order so should be here tomorrow. Thanks for the help and please let me know if you think of anything else. Graham
I just sall all your videos related to repair of this radio congrats a lot of great work you have put here. i got recently one as well and look like to have one issue frecvency nob is moving with some rezistence i could say and even if calibrate the frecvency for example on 1 MHZ calibrate (the electronic display with the dial) and by 2 Mhz already have discrepancy any suggestions? Thank you in advance!
Have you checked all the VCO voltages as they are likely to need adjusting.
No never. I own an frg100 a much later set. Looks like a promosing set to repair.
It will certainly be interesting. I've worked on a few older ham radios in the past and did have one of these for a short while but traded it for a JRC NRD-535. Got to find a frequency counter now
+Radiocruncher You could use the oscillator field of another receiver to generate an injection signal if you get stuck, though that generally is only of use for dial alignment :)
Thanks Dave. From initial finding the dial alignment is pretty much there. I did compare it with my Icom IC-7800 to verify the 20m band but haven't gone through all the bands yet
Do you have any idea how to change the S meter bulb in a 7700?
I think the S meter was about the only thing I didn’t take apart so can’t really help you there. Thanks for watching. Graham
PSU ripple?
Seems that it might be possible Simon. These have a reputation of the power supply failing. I ordered all the caps and a replacement bridge rectifier earlier so should be here tomorrow. You ever had one of these in?
AF117s, got to be 😁
If only! It's turning out to be a bit of a head scratcher.
+Radiocruncher I bet. It's all offset IF and PLL and scary stuff like that. In the words of Frankie Howerd, 'Oooerr missus'
It's a bit of a minefield Andrew. Does seem like it's limited to part of the VFO circuit so more thinking required
HF