Rf output coax running past the filtering cap !!!

shuffy wrote:True but:

Uksoundz wrote:When I first power on the hum is loud for a second or so, it then dies off completely for another second before gradually re-appearing over another second or so and then staying continuous.

So sounds like the power output (and therefore input) are changing over the VCO lock-up period, which is leading to either an RF induced effect, or an issue with the PSU regulation.

I think this was the closest. I PMed the guy and got him to measure the PLL voltage which was about 1v where it should have been 2.5v in the middle of the lock range. If the PLL was close to one edge it would sound like a car revving up and also explain the rig being 50KHz off frequency. Maybe the core of the tank became loose in transit to the UK?
Understandably the OP decided to send the whole thing back to Holland rather than messing around inside it having got some advice from a random on RN!

Haha fair point I did think that me messing around would be a bad idea!! Still haven't heard anything back from him yet though, hopefully I'll get it back soon!

Hello Uksoundz!
Nice neat lil rig you have there!
A couple of things though? it seems the audio input to the PLL is very close to the fan?
also ive never liked the idea of a stereo encoder so close to PSU and rf section without sheilding?
Have you treid disconnecting the encoder to see if it eliminates noise in mono?

He's sent it off mate to be looked at by the builder, hopefully they will let him know what the problem was....