BeePre voltages off and LEDs light up on A side but not on B [resolved]

[Tubegopher]

Well, I thought I had done a good job of assembly but I have problems. I am not as good as I had assumed!   I am not getting any filament voltage on the 300Bs. I am getting filament voltage on the EL84s. The LEDs on A side light up, but not the B side. My voltages are off such as:

2 should be 90 to 110 and reads 160V
4 should be 9.85 and is 0
6 should be 146v and reads 169v
10 should be 186 and reads 181v
11 should be 146 and reads 171v
15 should be 186 and reads 179
16 should be 5v and reads 0
17 should be 90-110v and reads 169v
19 should be 9.85v and reads 0
22 and 25 read 211V
29 and 30 should read 6.8v and read 7.7v
31 should read 13.6v and reads 12.4
34 should read 13.6 and reads 15.6
c3 and d3 should read 3.5 to 4.5v and read 1.8v
c7 and d7 should read 147v and read 173
c9 and d9 should read 147v and read 170
Other than that... I was perfect!

 

[Paul Birkeland]

What do you get at POS In and POS Out on each power supply board? 

 

[Tubegopher]

Paul, excuse my ignorance but what do you mean by POS ?
Thanks,
Don

 

[Deke609]

The filament regulator boards have holes labelled "Neg IN", "POS IN", "NEG OUT" and "POS OUT" -- along the outer edges of the long sides.

cheers, Derek

 

[Tubegopher]

Thanks Derek,
I will follow up now that I see what he was asking! 

 

[Tubegopher]

Paul,
I get the following:
Pos in A 15.4 B 12.2
Pos out A 10.4  B 7.6
Thanks,
Don

 

[Paul Birkeland]

Unplug the 300Bs and recheck POS Out on both sides.  The voltage at POS out A indicates that the 300B it feeds should be lit up, is it lit up? 

The 7.6V at Post Out B indicates a fault that would have to be addressed before anything else is examined.

 

[Tubegopher]

Thanks Paul, I will look into it tomorrow. I have had a couple of glasses of wine ... Will wait!

 

[Tubegopher]

I have spent some time checking connections and solder joints and re-touched many solder joints.
The current voltages for Pos in and out with no 300B installed are:
For A Pos  in 15.7 Pos out 10.4
For B Pos in 13.8  pos out 7.8

Neither of the 300B tubes are lighting up at all.

One thing I noticed and I can't find where it said to do this is:
There is an interconnect bare wire connecting terminal 24 to 23 on A side and
terminal 41 to 42 on B side. Should these be there or was this a mistake?

 

[Paul Birkeland]

Yes, those interconnections need to be there. 

Your B side seems loaded down even with no tubes installed.  This could be from a backwards 10,000uF cap up by the socket, swapped transistors on the noise filter on the power supply board, or some other miswire.  This will be something different between the working side and the non working side.

The A side board will light up a 300B, it's just not that easily seen.

 

[Tubegopher]

Paul, you were right. There was a significant mis-wire that I did and it has been corrected now . Thank you for all of your help! I have now listened to several vinyl records and a couple of CDs and I am truly blown away! My wife has better ears than me and she is shocked at the amount of improvement over our previous preamp!  Our turntable now truly sounds better than our CD player and that is partly due to the Eros phono preamp! So glad to have found Bottlehead!  ;D