I look forward to seeing what the spectrum analyser comes up with. I did observe that the RF TX power was causing the TX power meter to move (AMing), which is not ideal. The RX performance, however, seems well above average. Back in the day, my dad ran an early one of these as his "daily driver" mobile, with mum using a Mustang 3000 back at base. Very solid performers over several years.
Good Scratchy corner test until 5 mile point but seemed to weak there and after, but I have read the comments prior to my post and we know why that was which is what the tests are for catch you on the next one 10-10.
I agree. Just had it on the spectrum analyzer & discovered the first transmit mutiplyer wasn't at peak. This proves how you need to go through all the alignment several times...which I did...but with hindsight should have re-checked the earlier stages again once I'd adjusted the 2nd harmonic trap coil (next to last one). This is why we ALWAYS have done air tests on business radios & CB radios alike. We catch about a 2% failure rate this way. Obviously this set had an awful lot wrong with the transmitter so wasn't a 'normal' alignment. There will be a "Commtron 40F revisited" video which will include a partial 'on the air' retest....yet to be recorded. Richard, G0OJF, UK
@@ukfmcbradioservicingTango21 I remember you having a similar scenario with a Great boarded set some time ago. Not to mention the "7 watts" screwdrivered ebay gems!
This is the early version with a non-adjustable S-meter. Luckily they spotted your comment from the future, went back to 1982 & fitted a meter preset on production from Feb 1982 onwards. I discussed all this on the repair video for this set, Richard, G0OJF, UK
I look forward to seeing what the spectrum analyser comes up with. I did observe that the RF TX power was causing the TX power meter to move (AMing), which is not ideal. The RX performance, however, seems well above average. Back in the day, my dad ran an early one of these as his "daily driver" mobile, with mum using a Mustang 3000 back at base. Very solid performers over several years.
Hi 👋 richard I enjoy your air test also best wishes to you and mr chippy from paul chapman at east sheen 73's
Thank you Paul,
Richard
@@ukfmcbradioservicingTango21 to richard you are most welcome From paul chapman at east sheen 73's
Good Scratchy corner test until 5 mile point but seemed to weak there and after, but I have read the comments prior to my post and we know why that was which is what the tests are for catch you on the next one 10-10.
As a previous comment said that radio does look good in black.....after the extensive repair I think that was a fair test of that radio .....👍
I actually think the black looks better than the original silver, looks more like a Maxcom 4E now
Seriously noisy day.
Sounds like 2w on 27 mhz and 2 watts on aircraft band. Something amiss that was way lower than usual.
I agree. Just had it on the spectrum analyzer & discovered the first transmit mutiplyer wasn't at peak. This proves how you need to go through all the alignment several times...which I did...but with hindsight should have re-checked the earlier stages again once I'd adjusted the 2nd harmonic trap coil (next to last one). This is why we ALWAYS have done air tests on business radios & CB radios alike. We catch about a 2% failure rate this way. Obviously this set had an awful lot wrong with the transmitter so wasn't a 'normal' alignment.
There will be a "Commtron 40F revisited" video which will include a partial 'on the air' retest....yet to be recorded.
Richard, G0OJF, UK
@@ukfmcbradioservicingTango21 I remember you having a similar scenario with a Great boarded set some time ago. Not to mention the "7 watts" screwdrivered ebay gems!
RX Scale setting shows too much gets on top full 9+30db ~ 100db
This is the early version with a non-adjustable S-meter. Luckily they spotted your comment from the future, went back to 1982 & fitted a meter preset on production from Feb 1982 onwards. I discussed all this on the repair video for this set,
Richard, G0OJF, UK