Please check my readings

fastbike · 2995

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Offline fastbike

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on: November 06, 2011, 03:54:34 AM
Thanks in advance. Built the kit w/ PJCCS. 2 changes to plans. After reading the forum, the bypass caps are 47uF 35V Elnas. The 2.2uF were replaced w/ ERSE polypro 2.0uF 125V.
Readings are consistent channel to channel, but seem a bit far off the spec.

Resistance :
1 1.5 ohms to 97.5 Kohms
2 997ohms
3 0
4 997
5 same as 1
6-10 0

Voltages:
1 0 vdc
2 1.741
3 0
4 1.789
5 0
6 18.04
7 27.28
8 0
9 9.01
10 0.001

A1 .204
A2 16.05
A3 0.001
A4 16.03
A5 1.739
A6 16.02
A7 .204

B1 .253
B2 15.9
B3 0
B4 15.94
B5 1.785
B6 15.92
B7 .253

I understand they won't exactly match the instructions, but these are more than a few percent.



Offline fastbike

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Reply #1 on: November 16, 2011, 05:20:21 AM
So 50 views and nobody has any opinions / advice or anything? Lot of talk about the Bottlehead community but no help?



Offline Doc B.

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Reply #2 on: November 16, 2011, 07:05:13 AM
So 50 views and nobody has any opinions / advice or anything? Lot of talk about the Bottlehead community but no help?


It might be that we don't understand exactly what measurement has initiated your concern. The best way to induce someone to help is if you post the number for a terminal listed in the manual, as well as the number you measure at that terminal, so that we don't have to go back and forth from the post to our copy of the manual to determine this. I am on my way in to the office and will take a closer look at this when I get in.

If the case is that you feel some values are on the low side, have you checked the voltage of your batteries?

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Online Paul Joppa

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Reply #3 on: November 16, 2011, 07:18:08 AM
The D cells are wired in reverse. It's an error in the manual; pins A1/A7 and B1/B7 should be 1.5v greater than A5 and B5 respectively. (This has come up a few times in the Quickie forum, but has not made it to "sticky" status yet.) This change will bring up the plate voltages (A2-4-6 and B2-4-6).

Still, your cathode voltages (T2 and T4, as well as A5, B5) are lower than they should be. Check the orientation of the bypass cap; if reversed it may be reducing the effectiveness of the cathode resistor.

Those are the only problems I see.

Paul Joppa