Hi Mal & LF,
I am using the G0MRF 300 watt Tx but since blowing several PA mosfets I
decided to carry out the M0BMU PA mods using the original toroid & I can now
run a cool PA up to 650 watts into dummy load bench testing. I put it on air
into antenna & started with 280 watts & on following tests gradually
increased to 420 watts (still cool) with antenna current up to 2.3 Amps it
was at this time I got corona/arcing on the spiral top load so I stopped
tests until I have the time to lower the mast & carry out a visual
inspection of the area of arcing so as to effect a cure. I suspect that I
may have too little clearance between the spiral & the metal fixing
hardware, an inspection will be carried when work & family permit.
Regards,
Gary - G4WGT - IO83qp
Web : http://myweb.tiscali.co.uk/wgtaylor
-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of hamilton mal
Sent: 28 March 2005 12:27
To: [email protected]
Subject: LF: Re: Re : tests.
----- Original Message -----
From: "Gary - G4WGT" <[email protected]>
To: "LF (Rsgb LF Group)" <[email protected]>
Sent: Tuesday, March 22, 2005 9:26 PM
Subject: LF: Re : tests.
Hi All at LF,
Had to cease tests as I saw arcing on the spriral top load several times,
it
has been raining today so it may be due to the wet on the spiral or
possibly a problem with the higher power or a combination of both. I will
keep you informed.
Regards,
Gary - G4WGT - IO83qp
Web : http://myweb.tiscali.co.uk/wgtaylor
Hi Gary
What sort of PA have you now got. There was some discussion earlier about
Cap and Res values etc so what values did you find optimum.
73 de Mal/G3KEV
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