[ICOM] IC730

[HENRY PFIZENMAYER]

Alan -- I just Googled the 2SC1945 --- something is very strange -- the web
sites say the 2SC1945  is a RF xsistor in a TO220 like package --- The
MRF317 according to my data book is NOTHING like that - its in a case 316-1
style 1 which is a Beo Flange package with a half inch ceramic (alumina)
cap.  So if you have something marked  MRF317 in a TO220 type package - , I
don't know what you have or where it came from - Must not be a MOT
transistor -

Incidentally , I don't know what ICOM gets for that part , but one of the
web sites in Holland I think it was had them for $12 or $13 US.

Rgds--- Hank K7HP



----- Original Message ----- 
From: "Alan Hughes" <zl3kr at ihug.co.nz>
To: "Icom mail" <icom at mailman.qth.net>
Sent: Wednesday, December 29, 2004 7:04 PM
Subject: [ICOM] IC730


> I have an IC730 which has had a problem of blowing the final
> transistors. I have carried out some modifications recommended
> that could have caused the problem. A friend of mine in the USA
> sent me a couple of  transistors which he was told would work ok
> in the IC730. The oriuginals are 2SC1945, the replacements are
> MRF317. They are the same physically but I believe they are a
> considerably higher gain transistor designed for 50-60Mhz use.
> On installing them I find that the final is unstable which I assume
> is because of the higher gain.Can anyone suggest a suitable
> modification that I could carry out that would stabilise these
> please??   Failing this I guess I will have to bite the bullet and
> buy another pair of 2SC1945's  LOL.
> thanks   Alan ZL3KR
>
>
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