50 watt build problem no juice to V1 or V2 tubes

Get support and show off your MetroAmp 50 Watt kit builds.

Moderator: VelvetGeorge

Post Reply
kevrockitt
Senior Member
Posts: 105
Joined: Sat Feb 28, 2009 11:00 am
Just the numbers in order: 7

50 watt build problem no juice to V1 or V2 tubes

Post by kevrockitt » Thu Jun 30, 2011 10:06 pm

Heys guys need some help with 50 watt build...tubes in V1 and V2 won't light up. Tubes test good. Voltage on pins 1 and 6 of V1 reads really high. Voltage on pins 1, 6 and 7 of V2 read really high. I have no reading at all at pins 3 and 8 of V1 or V2.
Everything on V3 checks out ok and the tube fires up. HELP!!!

Thanks
Kevrockitt

SteadyEddie
Senior Member
Posts: 1035
Joined: Wed Jul 07, 2010 11:55 pm
Just the numbers in order: 7

Re: 50 watt build problem no juice to V1 or V2 tubes

Post by SteadyEddie » Fri Jul 01, 2011 12:50 am

What about you heater filament voltage on pins 5 and 9?

User avatar
neikeel
Senior Member
Posts: 7231
Joined: Tue Dec 06, 2005 8:31 am
Location: Suffolk, England

Re: 50 watt build problem no juice to V1 or V2 tubes

Post by neikeel » Fri Jul 01, 2011 4:56 am

SteadyEddie wrote:What about you heater filament voltage on pins 5 and 9?
Yes, your heater wires have a dry joint or broken wire between V3 and V2
:wink:
Neil

kevrockitt
Senior Member
Posts: 105
Joined: Sat Feb 28, 2009 11:00 am
Just the numbers in order: 7

Re: 50 watt build problem no juice to V1 or V2 tubes

Post by kevrockitt » Fri Jul 01, 2011 8:24 am

I will check all heater wire connections. I have 3.15 AC voltage readings at 4/5 and 9 on all three pre tubes though. I will keep posting results. :-)

Thanks
Kevrockitt

User avatar
neikeel
Senior Member
Posts: 7231
Joined: Tue Dec 06, 2005 8:31 am
Location: Suffolk, England

Re: 50 watt build problem no juice to V1 or V2 tubes

Post by neikeel » Fri Jul 01, 2011 9:24 am

kevrockitt wrote:I will check all heater wire connections. I have 3.15 AC voltage readings at 4/5 and 9 on all three pre tubes though. I will keep posting results. :-)

Thanks
Kevrockitt
But you say your heaters do not light up, if you have ac volts the heaters should light up?

You will not get much voltage on pins 2 and 8 on V1 those are the cathodes

Pin 1 is the plate as is pin 6, so if V2 is reading high on the plates (1, 6 and 7) this suggests that your bus wire from the mid board filter cap or the second 10k dropper is open circuit.
Neil

kevrockitt
Senior Member
Posts: 105
Joined: Sat Feb 28, 2009 11:00 am
Just the numbers in order: 7

Re: 50 watt build problem no juice to V1 or V2 tubes

Post by kevrockitt » Fri Jul 01, 2011 10:13 am

Headin' to the bench to check that now. :-)

kevrockitt
Senior Member
Posts: 105
Joined: Sat Feb 28, 2009 11:00 am
Just the numbers in order: 7

Re: 50 watt build problem no juice to V1 or V2 tubes

Post by kevrockitt » Fri Jul 01, 2011 11:28 am

OK...checked all bus wire....all good. So I replaced the heater wire run from V3 to V1.
Valves are firing! Everything is checking out fine now thanks to my fine friends on the Metro Forum.
Once again you guys come to the rescue!!!!
Thank you guys so very much!!!
Kevrockitt

Post Reply