Taylor Model 68A

[Sinewave]

Originally Posted by Bazz4CQJ

Yep, 127 sounds better than 320. As mentioned above, the one thing I did try to do was to do a home conversion to make nine like a 68A model with the meter and level control. I managed to find a meter which I thought was suitable and fitted nicely behind the small window on the top RHS, but, for some reason, it didn't work out. I may give it another try during the winter.

B

That's the 68A/M. Though that meter would certainly be useful. Maybe we could look at the drawings and see where you got to?

If you made some modifications to the drawing, feel free to put them on this thread and maybe we could work through it.

[Bazz4CQJ]

Let me dig out the notes which I (hope) I made. My recollection is that the meter which I used never showed more than about 30% deflection. IIRC, the manual for the Taylor did not show specs for their meter, but I took my lead from a more detailed manual I had for a sig gen made by Advance, also using a 12AT7 oscillator.

I think the pot I used for the level control was a fairly run-of-the-mill Colvern wire-wound and the chassis has a hole pre-drilled to take that that. It was quite easy to solder in a diode inside the can which screens the 'RF Output' pot and route that out to the meter. Apart from the fact that it didn't work, it was a very straightforward job

B

[Bazz4CQJ]

I found the notes, but they are not as helpful as I'd hoped. Attached is a PDF outlining what I did in terms of adding the meter. I used a GEX66 diode, which seemed to be a fair choice as was the 100uA, 1720R meter.

As you'll see from the Instruction Manual, the level control is effected purely by adjusting the HT on the oscillator and to do that I wired in a circuit centered around a 20k wire-wound pot.

I didn't manage to figure out why the mods did not work, and as another sig gen was available, I gave up on it after a certain amount of time.

I found that there was some RF escaping from the oscillator box and getting out down the mains lead. My notes show that I achieved some improvement by adding a 0.01uF disc ceramic decoupler on pin 1 of V2A (it was just a an easy place to add the capacitor) and another one across C24, the HT smoothing cap.

B