UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Heatercathodeshort · 18th Mar 2019, 6:36 pm

I very much like the Thorn 600 series. Very reliable and they give a brilliant picture.

It is unusual David to discover the alignment has been twiddled in the very stable 600. This was a common problem in the late 50's and early 60's often carried out by the old school 'Radio Men' that did not understand the principles of vision AGC, still thinking that the contrast control adjusted the gain of the RF amplifier.

A simple 6DB attenuator would have cured the sound on vision but oh no, they just had to twiddle those I.F. cores often smashing them and jamming them in the coil formers.

Every Philco 1000 and 1019 models were twiddled beyond belief followed only by the Sobell series with the useless FM radio. The Sobell models were great receivers but suffered from the phantom twiddler more than other models.

A few spot frequencies and the service manual should soon sort that out David. We now have the use of frequency counters so no excuses for not making a first class job of it.

Don't be cruel to the poor little wire wound resistor, it is 60 years old..
Regards, John.

18th Mar 2019, 6:36 pm	#4
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Ferguson 705T Senator. I very much like the Thorn 600 series. Very reliable and they give a brilliant picture. It is unusual David to discover the alignment has been twiddled in the very stable 600. This was a common problem in the late 50's and early 60's often carried out by the old school 'Radio Men' that did not understand the principles of vision AGC, still thinking that the contrast control adjusted the gain of the RF amplifier. A simple 6DB attenuator would have cured the sound on vision but oh no, they just had to twiddle those I.F. cores often smashing them and jamming them in the coil formers. Every Philco 1000 and 1019 models were twiddled beyond belief followed only by the Sobell series with the useless FM radio. The Sobell models were great receivers but suffered from the phantom twiddler more than other models. A few spot frequencies and the service manual should soon sort that out David. We now have the use of frequency counters so no excuses for not making a first class job of it. Don't be cruel to the poor little wire wound resistor, it is 60 years old.. Regards, John.