Hi Gary Ah that won't give any trouble, just make sure you have enough
"headroom" for the 3 legged reggies....4v should be enough but marginal if
you have droop under load. You have nothing active in the main supply to
take exception to strange loads. I think there is an electronic fuse on Dave
G3YXM's site that might be useful.....I dont know whether you would sense a
supply current increase before the failure.
Alan
----- Original Message -----
From: "Gary - G4WGT" <[email protected]>
To: <[email protected]>
Sent: 05 July 2005 20:37
Subject: LF: RE: Re: RE: G0MRF 300w Tx PA mods
"What sort of PSU is it ??"
It is a simple affair using a big toriod transformer, 40V x 40V at 6.3A
500VA with windings in parallel smoothed by 2 x 10,000MFD 100V capacitors
(voltage is about 45V before going to transmit state) & a smaller toroid
to
supply about 28V DC to 24V & 12V 3 leg IC regulators within the
transmitter.
I am only using the variac at present because I wanted to bring it up
gently
until I was sure that all is well, I will need to fit some sort of soft
start when I am happy with it & know I can run it at max volts, I can then
remove the variac.
Thanks for your feedback.
Regards,
Gary - G4WGT - IO83qp
Web : http://myweb.tiscali.co.uk/wgtaylor
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