View Single Post
Old 28th Sep 2018, 3:53 pm   #38
crackle
Rest in Peace
 
Join Date: Mar 2011
Location: Basildon, Essex, UK.
Posts: 4,100
Default Re: Building the 'Minimod' AM modulator-questions!

I have come to the conclusion that the frequency drift happens regardless of if the Minimod is switched on or not.
I set the frequency dead on 1071kHz and then turned it off, went back to it a couple of hours later and turned it on, the frequency was 1076 kHz
I have experimented with screwing the ferrite core right down to the bottom against the paxolin. The frequency was in the region of 1640 and when I came back later it was on 1641kHz. I am going to look for some strands of knicker elastic and try to jamb that in the threads of the ferrite, I am hoping it will force the ferrite over so that the threads mesh together tightly so there is no play for it to move.

Mike
crackle is offline