GW4ALG's Drake TR7 Pages

[ GW4ALG went QRT in February 2007 ]

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A picture of the author

I'm Steve Rawlings, holder of the amateur radio callsign 'GW4ALG'.  

Through these pages, you can read about the modifications that I carried out on my Drake TR7 transceiver.  These notes should be read in conjunction with the Drake TR7 Service Manual.

I sold my TR7 in about 1980, but I know that the modifications that I wrote up all those years ago (when I was G4ALG) are still of interest.

My thanks to all those who contributed ideas and suggestions.



Update: July 2003
1) Does anyone know of an organisation in the UK offering repair services for the TR7?
2) For pictures of the TR7, see:

Update: September 2004
Regarding QRP operation, Nigel G8IFF writes:
"Setting a TR7 for QRP is relatively easy. Turn the ALC pot down (I think it's on the driver board). Having had blown up PA transistors on mine, I've set mine for 100W out on all bands and use a speech processor.

Alternatively, the driver board probably runs a watt or so without the PA module. (Then, whoever wanted to know, can send me his PA module to use with my FT-817!)"

Update: August 2005
Regarding Modification No. 8 (LF Coverage) Marcus PA0MLC writes:
"In order to improve the sensitivity of the LF frequencies one may remove the 20 dB attenuator which is inserted in the RF path when using the LF antenna input.  However, care must be taken as RF feedback during TX via this path is now (without the 20 dB att) very much likely.  Nevertheless, the improvement of the sensitivity is worthwhile, in my opinion."

Steve Rawlings, GW4ALG
7th August 2005