Hello Mike,

Friday, October 30, 2015


yes, I still have trouble with the workshop alarm going off when I TX,
but seemingly only at night, for whatever reason! Isolation is
something I need to add. I have a 3C90 core spare and will wind a 1 :
1 transformer for now, just for isolation. How many turns should I use
for best efficiency? I will probably use either 1.5 mm enamelled wire,
or maybe some Teflon covered stuff.

I also need to tame the variometer, it's obviously got far too many
turns on it as just a couple of degrees moves resonance a long way. I
picked up a 2 axis variometer, possibly a goniometer, that I may ise,
with a motor drive. Photos at http://www.chriswilson.tv/goniometer.zip

I only gave a fiver for it, so no big deal if it doesn't work out, but
I am about to check what inductances it covers. I think it should
withstand the voltages OK. What do you reckon? It would be easier to
motor drive then the variometer in my loading coil.

Thanks for the kind words about my progress. Most thanks should go to
G3YXM for helping me get my amp done and reliable, he's been a
Godsend, as have you gentlemen on here.


> I agree with Stefan. A transformer (using a suitable core material 
> such as 3C90) gives you more flexibility in the future It also 
> provides the opportunity to isolate the RF ground from the mains 
> supply ground which can improve EMC both on transmit and receive.

> Well done so far. Your signal is very impressive with such low RF 
> power.

> Mike, G3XDV
> ==========







-- 
Best regards,
 Chris                            mailto:[email protected]