UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - FM to AM converter

crackle · 27th Sep 2018, 4:42 pm

Hi David / Derek
Is there any problems with frequency drift with this little AM TX.
I built a Minimod as an experiment but have put it aside as it suffered rather from frequency drift.
So after an hour or so you would need to retune the radio. I was using a Synthesized radio so I don't think it was that wandering off tune.
One other radio I was using was also synthesized but in multiples of 9kHz so that was not helpful at all when the Minimod TX drifted.
I tried to use quality components and I tried various types of cap in the tuned circuits including mica and ceramic, some drifted more than others.

Mike

27th Sep 2018, 4:42 pm	#14
crackle Rest in Peace Join Date: Mar 2011 Location: Basildon, Essex, UK. Posts: 4,100	Re: FM to AM converter - variation on a theme! Hi David / Derek Is there any problems with frequency drift with this little AM TX. I built a Minimod as an experiment but have put it aside as it suffered rather from frequency drift. So after an hour or so you would need to retune the radio. I was using a Synthesized radio so I don't think it was that wandering off tune. One other radio I was using was also synthesized but in multiples of 9kHz so that was not helpful at all when the Minimod TX drifted. I tried to use quality components and I tried various types of cap in the tuned circuits including mica and ceramic, some drifted more than others. Mike