Wanted push button tuner for RGD 612 TV

[regentone001]

A long shot I know but does anyone have a spare push button tuner for the RGD 612 which is the same as the Regentone 17-18 and Argosy17-K-10 TVs
I believe it is very similar to the Cyldon tuner used in later RGD Regentone sets but was not known for it's reliability. The one I have the mechanics are fine but something went out in a cloud of smoke in the electronics so I am looking for either a complete unit or one for spares
Thanks in advance
Steve

[Vintage Engr]

Is that the one with the rectangular buttons & plastic slider for the incremental tuning?

David.

[regentone001]

Hi David
it has 4 sliders, one for each button, that slide across some connections for each channel it looks like this one in the picture attached
Steve

[Vintage Engr]

I knew it well, that is around 60 years ago! Rediffusion also used them in their Aerial versions of the MK7 TC, the '"Sheerline" range.
We got so fed up with them failing, that I made an 'unauthorised" modification, & fitted a small NSF/Pye rotary tuner instead.

These push-button tuners are really scarce now, as I found out when helping another member, - now a friend, on the forum.

I eventually made up a replacement (his was missing) using an ELC1042 (VHF) varicap tuner together with a home-made pushbutton switch bank that bolted neatly into the original chassis. This worked perfectly & from the outside looks correct.

You say that yours is mechanically o.k. -I presume you have enough plastic sliders to make it function, i.e. more than one, so you have a spare?

If this is so, then you are probably better off repairing the tuner. They can successfully be repaired as long as you have the sliders, the coils are all there, & the contacts still o.k.
Worth a try. I might be able to help if you have a problem.

David.

[regentone001]

Hi David
I have just dismantled the tuner and removed the printed circuit board. 3 Resistors measure incorrectly, one reading totally open circuit. I was worried that one of the coils may have burned out but, touch wood, they look ok. So I will replace the resistors and see what happens. The HT connector was cracked and broke off as I dismantled it so I will have to hard wire it but as I have it apart anyway that is not a bog problem.

Steve

[Vintage Engr]

I've just had a look at the circuit of the tuner. From a very distant memory I recall that the screen resistor on the mixer, R12; 22K used to go. Could be it just gave up, or a leaky C19.
The valve sometimes caused the problem. The other resistor that used to burn & go high, was the 6.8K anode feed, note that this is external to the actual T/U, but may be mounted externally on it, or in the case of the RGD/Regentone, on the main chassis. Note that the anode feed for the mixer is fed via the I.F. output coil.

Check R7, the anode feed to the VIb, and also C11.

I can't think of anything else at the moment, I probably could if I had the tuner in front of me! Good luck,

David.

[Vintage Engr]

I 've just thought, you might like to move this out of the 'wanted' section, into the TV section, as it's no longer a 'wanted' item, & we don't want to wander off topic!

David.

[regentone001]

Mods could you please move this thread to the tv repair section thank you