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Get both trimmers to their mid-points... A/DAade the way these are adjusted kind of strange. The cRange trimmer adjusts how wide the difference is from min. frequency on the sweep to the highest frequency is on the sweep. The cMax trimmer adjusts what the max frequency is of the sweep.
So if you're getting 1.2mHz, check what the min frequency is of your sweep. If it's much below what the minimum frequency is supposed to be, then the cRange trimmer needs to be adjusted to bring the extreme ends of the sweep closer together.
It's kind of hard to explain... CRange adjusts how wide the frequency sweep will be. CMax adjusts how high the highest sweep frequency will be.
Hope this helps.

That looks right. Please report back when you get it running!

No, just use pins 2&3 on the C500k pot... "Send" goes to pin 2 of pot, "return" goes to pin 3 of pot so CCW of pot gives you attenuated dry signal and CW gives you full dry signal. I used C500k with my A/DA TZF, if C500k doesn't attenuate dry signal enough, use a C1M pot.
You shouldn't need to use switching when this mod is implemented, just use the pot for how much dry through signal you want.

Hi again,
I looked at the CL build sheet and see what you're talking about. I had missed what "S" & "R" were... Makes sense now... Yes, your diagram should work. One more question: What is the small board with the op amp on it? Is that used for inversion or to boost signal?
One more thing... On CL board #2, dont connect the S/R together, you dont want dry signal being fed to the output. Dry through signal will kill any TZF sounds. What I'd do on CL board #2 is put a C500k pot between S&R pads so you can have dry signal but you can also dial the dry signal out. So  for TZF, use the pot to dial out dry signal, for dual comb filter nirvana, dial some dry signal in.
Hope this helps.

I can't really follow your drawing but what needs to be done is to put the delay line from board #2 in place of the dry through signal on board #1. The current lover should have a place on the board where you should be able to do what you want.

Dissipation of the regulator is voltage drop within regulator (Vin -Vout) X current going through regulator. So, if the regulator is dropping a lot of voltage and pulling close to 100ma the L reg may get excessively warm. You can always get se a standard TO220 version, they don't take up much more space than an L version

I like Scruffie's gain setting instructions from Lectric FX...
Basically,  inject a 1kHz audio signal into the input of your total recall and measure it's amplitude before clipping (in millivolts). Now measure the amplitude of the signal at pin 7 of the compander and adjust "gain 1" to get it as close to the input amplitude. I was never able to get it equall to input amplitude but I can get it close...
Next, take amplitude measurement of pin 15 of the compander and use "gain 2" to adjust so it's equal to input amplitude. You should be able to get it exact.
Doing this, I find that the feedback control has a lot of useful range.
Hope this helps...

It sounds like you need to adjust the two trimmers... Start at the mid-point on both trimmers. One trimmer sets overall brightness of the lamp and the other trimmer sets the offset, which is basically how dim the bulb gets.

That's an old school Signetics 571, the original manufacturer of the 57X companders. Philips bought them out in the late 80s or early '90s.
His 4047 is from the 80s. If they are known good ICs, they will work well in that circuit.

The CA3094 is a noisy IC. When it originally came out, most circuits were noisy compared with what's available today. The LM13700 is superior in every way to the CA3094.
IDK why people get so twisted about rolling different op amps in their circuits...

The 5R4 rectifier while only having a 2amp heater draw, so in that sense comparable to 5Y3, it has as first filter cap allowance according to datasheet only 4uF max rating for first node filter cap, so that might be a problem if you substitute that in.

Wow! I never checked that. Makes sense though as the amp I saw them in was an old Altec 1570B which uses a 6uf oil cap.
Thanks for bringing it to my attention

Those blue drop caps are notorious for becoming leaky. The tone ones aren't that critical but the one in the attached pic that feeds the 6V6 is. Take voltage measurements on both sides of it with reference to ground. The 6V6 side should be at ground (0v).
Also, see what you can get a 5R4 rectifier tube for... They are beefy yet only take 2 amps filament current like the 5Y3. I wouldn't use the GZ34 because of the voltage increase.

Email SC, they will exchange for good ones. I bought 10 of those a while back during one of their sales and one was bad. They replaced it.
BTW, NOS is misleading... Most of what I got were working pulls. Ok by me as they tested ok.

Why even bothering announcing something pretty major, and then recanting it two days later???


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That's what Mike Mathews does... He's a total shyster...
He got a marketing degree from Harvard... Yes, really...

Yes! You are correct, sir!