Simplistic NJFET RIAA

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TP1/TP2 will be reverse climbing with temperature. Set it with closed case after 30 mins eventually. Because it will be difficult to monitor when closed, just hang two crocks out of the box each one clipped to C3 input side per channel. Measure between each crock and ground lug for TT sporadically. Find some initial B+ that allows for 4V between those crocks and GND when box is well warmed up and lid is on. Accuracy is not a problem, just to be hovering there about.
 
What I'm afraid of is my LED sets. I set it up with 18.X v (12 AA alkaline) and 2SK117GR (close one to what I used for Q7 (4.65mA). I came up as 2 red and 2 green LEDs. I do not see that anyone else uses such sets. I have hesitations now and maybe I did not measure these correctly.
In addition, I use 2SA970BL (not BC560C..). As you clammed, it should be better.
 
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I got Cardas Quad, Siltech Silver AA, various silvered EU ones, 60/40s, and Chinese eutectic. I used the Chinese in the prototype because it was handier at 0.5mm Diam.:)

Use Cardas if you worry about that thing. Not much fuming, good response, good metallurgy, smells nice.
 
diyAudio Chief Moderator
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What I'm afraid of is my LED sets. I set it up with 18.X v (12 AA alkaline) and 2SK117GR (close one to what I used for Q7 (4.65mA). I came up as 2 red and 2 green LEDs. I do not see that anyone else uses such sets. I have hesitations now and maybe I did not measure these correctly.
In addition, I use 2SA970BL (not BC560C..). As you clammed, it should be better.

They did not reach my voltages with their LEDS so they opted for just matching between them strings and approaching noted values than mixing colors to be dead on. One Irish build mixed though. No big deal, maybe they end up with bit lower needed B+ and fraction of dB less gain than in the proto.
 
They did not reach my voltages with their LEDS so they opted for just matching between them strings and approaching noted values than mixing colors to be dead on. One Irish build mixed though. No big deal, maybe they end up with bit lower needed B+ and fraction of dB less gain than in the proto.

I see.
So, I should be fine.
The most important, they matched for L and R channels.
Right?
 
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Right. Good choice on solder.

BTW I always make protos with average to plain parts even. My notion is, if it does not cut it in the humble it will never be suave enough in gold pants. But you guys do as you aspire for that extra bit of finesse, me I just test the most important angles. Securing the base.
 
Right. Good choice on solder.

BTW I always make protos with average to plain parts even. My notion is, if it does not cut it in the humble it will never be suave enough in gold pants. But you guys do as you aspire for that extra bit of finesse, me I just test the most important angles. Securing the base.

I'm really appropriate your experience. Thank you again.