Mylithra

Re: [BUILD] CAPI VP28~500 Series~2-Stage Preamp~Official Support Thread
« Reply #980 on: December 31, 2018, 08:22:59 AM »

Yeah though I walk through the valley of the shadow of death I will have at my side a good solder sucker.
Anything else.....  not really, go slow learn and enjoy!


Get a Hakko 808 or FR-301. It will change your life.


JRoulat

Re: [BUILD] CAPI VP28~500 Series~2-Stage Preamp~Official Support Thread
« Reply #981 on: December 31, 2018, 12:18:31 PM »
Many thanks for the recommendation.

Re: [BUILD] CAPI VP28~500 Series~2-Stage Preamp~Official Support Thread
« Reply #982 on: January 14, 2019, 11:50:34 AM »
So with a 400HZ test tone being injected at 1.228V, and all settings correct for the test I have the following results.

TP1 - 111.8
TP2 - .998
TP3 - 1.804
TP4 - .450
TP5 - .450
TP6 - .450
TP7 - .940
Output at pin 2 is 1.402

Im not sure why they are higher than the guide, but they look close. Are these acceptable values?
:bump:
P&P Sound Studio

jsteiger

Re: [BUILD] CAPI VP28~500 Series~2-Stage Preamp~Official Support Thread
« Reply #983 on: January 14, 2019, 02:39:04 PM »
Have you confirmed that you have 1.228V AC when probing between pins 2 and 3 of your signal generator XLR? You cannot verify this level by referencing high or low to ground.
Visit the CAPI store at http://www.capi-gear.com

CAPI is not affiliated with, endorsed by, or sponsored by API.

Re: [BUILD] CAPI VP28~500 Series~2-Stage Preamp~Official Support Thread
« Reply #984 on: January 15, 2019, 06:02:09 PM »
Have you confirmed that you have 1.228V AC when probing between pins 2 and 3 of your signal generator XLR? You cannot verify this level by referencing high or low to ground.
Fluke 87 says 1.228 between pins 2 and 3
« Last Edit: January 15, 2019, 06:05:24 PM by Chrome Heart »
P&P Sound Studio

jsteiger

Re: [BUILD] CAPI VP28~500 Series~2-Stage Preamp~Official Support Thread
« Reply #985 on: January 15, 2019, 09:51:16 PM »
Fluke 87 says 1.228 between pins 2 and 3
OK. What opamps are you using? If they are built from kits, have you verified they are working properly in another know to be working properly module?
Visit the CAPI store at http://www.capi-gear.com

CAPI is not affiliated with, endorsed by, or sponsored by API.

Re: [BUILD] CAPI VP28~500 Series~2-Stage Preamp~Official Support Thread
« Reply #986 on: January 15, 2019, 10:25:06 PM »
OK. What opamps are you using? If they are built from kits, have you verified they are working properly in another know to be working properly module?
They are GAR 2520 OPAMPs built from kits. I did swap them out with a pair from another build and got the same results.
P&P Sound Studio


 

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