When does it blow the fuse?
1. When plugged in?
2. When the power switch is thrown?
3. When the Standby switch is thrown?
Gary
new build is now happy
Moderators: pompeiisneaks, Colossal
-
glasman
- Posts: 1446
- Joined: Wed Jan 19, 2005 10:37 pm
- Location: Afton, MN (St Croix River Valley)
- Contact:
Re: new build is now happy
Located in the St Croix River Valley- Afton, MN
About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
-
dcribbs1412
- Posts: 1386
- Joined: Wed Jun 11, 2008 6:56 pm
- Location: Arizona Desert
Re: new build is now happy
Thanks guys really appreciate every-ones time
T Wilcox...using a 120v light connected to HT
PT is from jborders5
not using fil resistors
very much appreciate the offer Gary...I'm in Parker
wish it was a quicker trip to Mesa
fuse blows when Standby switch is thrown...
...when I plug in power I can hear a soft hum in speaker...no switches on...
throw power switch...hum is a little louder, power light comes on...
throw standby switch...loud hum and fuse pops...
I've surely done something silly in my wiring
Darin
T Wilcox...using a 120v light connected to HT
PT is from jborders5
not using fil resistors
very much appreciate the offer Gary...I'm in Parker
wish it was a quicker trip to Mesa
fuse blows when Standby switch is thrown...
...when I plug in power I can hear a soft hum in speaker...no switches on...
throw power switch...hum is a little louder, power light comes on...
throw standby switch...loud hum and fuse pops...
I've surely done something silly in my wiring
Darin
Re: new build is now happy
Hey Man,
Thats a nice looking build!!!! Congrats, I am in no way an expert, but sometimes a fresh set of eye's can help.
I see a few things that could be an illusion...or the photo...hard to tell but
I see a few joints on the rectifier board that don't appear to have solder in them....again might just be the picture....
The other spot is the very 1 st photo you posted there is the 1.5 k resistor on the socket, below it is an Thick orange wire...below is a blue wire...
That orange wire looks like it might not be soldered in there as there is a fair amount of solder below the wire......That area in the amp is very hard to get to most of the time......also check to see that you don't have any trimmed off pieces of wire laying across a tube socket....this would blow the fuse every time.
Again more talented people than me have given suggestions, just go slow....probably something very simple....Great looking build!!!
Chris
Thats a nice looking build!!!! Congrats, I am in no way an expert, but sometimes a fresh set of eye's can help.
I see a few things that could be an illusion...or the photo...hard to tell but
I see a few joints on the rectifier board that don't appear to have solder in them....again might just be the picture....
The other spot is the very 1 st photo you posted there is the 1.5 k resistor on the socket, below it is an Thick orange wire...below is a blue wire...
That orange wire looks like it might not be soldered in there as there is a fair amount of solder below the wire......That area in the amp is very hard to get to most of the time......also check to see that you don't have any trimmed off pieces of wire laying across a tube socket....this would blow the fuse every time.
Again more talented people than me have given suggestions, just go slow....probably something very simple....Great looking build!!!
Chris
Re: new build is now happy
Darin,
Looks great! Based on your symptoms, I would probably pull off the rectifier board nuts and see if you had some solder drippage while soldering on the orange looking(probably red) wires from the PT. There are a lot of ceramic caps there in close proximity as well. Maybe something is touching in there. You shouldn't get any sound with standby off so something maybe is amiss in that circuitry area.
Looks great! Based on your symptoms, I would probably pull off the rectifier board nuts and see if you had some solder drippage while soldering on the orange looking(probably red) wires from the PT. There are a lot of ceramic caps there in close proximity as well. Maybe something is touching in there. You shouldn't get any sound with standby off so something maybe is amiss in that circuitry area.
-
glasman
- Posts: 1446
- Joined: Wed Jan 19, 2005 10:37 pm
- Location: Afton, MN (St Croix River Valley)
- Contact:
Re: new build is now happy
First.
Disconnect the B+ feed to the output tranny off of the power supply board. See if the problem still exists.
Use an ohmeter and measure between B+ and ground. Has to be after the standby switch and something is touch ground.
Also check the B+ feed to ground while you have it disconnected.
All of the above should read infinity, anything less is no good.
Gary
Disconnect the B+ feed to the output tranny off of the power supply board. See if the problem still exists.
Use an ohmeter and measure between B+ and ground. Has to be after the standby switch and something is touch ground.
Also check the B+ feed to ground while you have it disconnected.
All of the above should read infinity, anything less is no good.
Gary
Located in the St Croix River Valley- Afton, MN
About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
Re: new build is now happy
You've gotten a bunch of great suggestions.
I can see several questionable solder joints. Spend time to get the solder joints perfect, no excess solder, nice tightly wrapped connections and enough heat to leave a smooth shiny joint.
Good luck
I can see several questionable solder joints. Spend time to get the solder joints perfect, no excess solder, nice tightly wrapped connections and enough heat to leave a smooth shiny joint.
Good luck
-
dcribbs1412
- Posts: 1386
- Joined: Wed Jun 11, 2008 6:56 pm
- Location: Arizona Desert
Re: new build is now happy
Hey guys
Had a chance to try a few things
disconnected the OT as suggested and hum but no blown fuse...
disconnected the rectifier board hum but no blown fuses
disconnected B+ to rec board hum no blown fuses..
so must be something with the power supply?
no visible shorts
I have an another PPS board...thinking about building new one...
as always any and all comments are greatly appreciated
Darin
Had a chance to try a few things
disconnected the OT as suggested and hum but no blown fuse...
disconnected the rectifier board hum but no blown fuses
disconnected B+ to rec board hum no blown fuses..
so must be something with the power supply?
no visible shorts
I have an another PPS board...thinking about building new one...
as always any and all comments are greatly appreciated
Darin
Re: new build is now happy
Your amp looks very similar to mine and i've been comparing photos of yours and mine and haven't seen anything out of the ordinary yet.
Where did you get your 330mf caps? I couldn't find an 330mf axial like that.
Where did you get your 330mf caps? I couldn't find an 330mf axial like that.
-
dcribbs1412
- Posts: 1386
- Joined: Wed Jun 11, 2008 6:56 pm
- Location: Arizona Desert
Re: new build is now happy
Thanks for checking CHIP
got the caps from Ceriatone
wondering if I may of got a bad OT?
not sure how to check...
Darin
got the caps from Ceriatone
wondering if I may of got a bad OT?
not sure how to check...
Darin
Re: new build is now happy
Darin, did you check B+ to ground as Gary suggested?dcribbs1412 wrote:Hey guys
Had a chance to try a few things
disconnected the OT as suggested and hum but no blown fuse...
disconnected the rectifier board hum but no blown fuses
disconnected B+ to rec board hum no blown fuses..
so must be something with the power supply?
no visible shorts
I have an another PPS board...thinking about building new one...
as always any and all comments are greatly appreciated
Darin
Re: new build is now happy
Check carefully the eyelets on the precision supply board where the wires from the B+, Choke, Screens, make sure those wires are in the correct holes.
I can't see the standby switch wires very well.
Make sure they go in the correct holes.
In the future you should first power up the amp with no tubes and use a light bulb current limiter to avoid blowing up expensive parts.
I like to to the first no tube power up with a 25 or 40 watt bulb limiting the amp to around 250ma.
My 100w ODS uses a 5 amp slo blo fuse on the mains.
I don't think 3 amps is big enough.
Your pilot light is 120vac I assume?
I was trying to figure out why you had the diode and resistor there for the LED pilot light.
Nice neat looking build, I'm sure it is something simple that will get you going.
I can't see the standby switch wires very well.
Make sure they go in the correct holes.
In the future you should first power up the amp with no tubes and use a light bulb current limiter to avoid blowing up expensive parts.
I like to to the first no tube power up with a 25 or 40 watt bulb limiting the amp to around 250ma.
My 100w ODS uses a 5 amp slo blo fuse on the mains.
I don't think 3 amps is big enough.
Your pilot light is 120vac I assume?
I was trying to figure out why you had the diode and resistor there for the LED pilot light.
Nice neat looking build, I'm sure it is something simple that will get you going.
Tom
Don't let that smoke out!
Don't let that smoke out!
-
groovtubin
- Posts: 1114
- Joined: Tue Feb 07, 2006 4:52 am
mains wiring
make SURE you don`t have your mains wiring wrong, it`s easy ta do...look at a fender twin/BF deluxe wiring schenme, ensure main`s primary`s aren`t in series w/ea other!!
-
dcribbs1412
- Posts: 1386
- Joined: Wed Jun 11, 2008 6:56 pm
- Location: Arizona Desert
Re: new build is now happy
Thanks guys
ground 1, ground 4, from standby, B+1 out, and to choke eyelets
Does the to standby eyelet go to top of standby switch?
Tom I had a 120v led so I used it after wiring the diode and resistor there for the LED.
as always thanks for everyone's time/effort
any comments are greatly appreciated
Darin
on the PPS board I'm getting continuity to ground on thedid you check B+ to ground as Gary suggested?
ground 1, ground 4, from standby, B+1 out, and to choke eyelets
Check carefully the eyelets on the precision supply board where the wires from the B+, Choke, Screens, make sure those wires are in the correct holes.
Does the to standby eyelet go to top of standby switch?
Tom I had a 120v led so I used it after wiring the diode and resistor there for the LED.
Thanks Tom still learning from my mistakes and everyone's comments/suggestions...Nice neat looking build, I'm sure it is something simple that will get you going.
as always thanks for everyone's time/effort
any comments are greatly appreciated
Darin
You do not have the required permissions to view the files attached to this post.
Re: new build is now happy
You should only have continunity to ground at those two notated ground points. Everything you need to troubleshoot this is right here.
To me it appears the filament, relay, HV/bias or screen supply are not shorted to ground. Just for giggles, verify that pin 6 of none the overhead screen resistors are shorted to pin 7 of the filaments. With no tubes, I don't think this would be an issue until the standby is flipped.
There's a commonality, all the places( from Stdby, B+1-OT, choke) that you shouldn't have a ground, are connected at the same point. This points me to the OT being shorted to ground at first glance.
On the PPS board, desolder only the OT from B+1 and then switch on the standby. If the fuse doesn't blow, check for voltages at B3-B5.
To me it appears the filament, relay, HV/bias or screen supply are not shorted to ground. Just for giggles, verify that pin 6 of none the overhead screen resistors are shorted to pin 7 of the filaments. With no tubes, I don't think this would be an issue until the standby is flipped.
There's a commonality, all the places( from Stdby, B+1-OT, choke) that you shouldn't have a ground, are connected at the same point. This points me to the OT being shorted to ground at first glance.
On the PPS board, desolder only the OT from B+1 and then switch on the standby. If the fuse doesn't blow, check for voltages at B3-B5.
-
dcribbs1412
- Posts: 1386
- Joined: Wed Jun 11, 2008 6:56 pm
- Location: Arizona Desert
Re: new build is now happy
Thanks ToneMerc
I will check voltages B3-B5 ASAP and report back...
Thanks for your time
Darin
will do ASAPverify that pin 6 of none the overhead screen resistors are shorted to pin 7 of the filaments
I have disconnected the OT from B+1 and fuse does not blow...On the PPS board, desolder only the OT from B+1 and then switch on the standby. If the fuse doesn't blow, check for voltages at B3-B5.
I will check voltages B3-B5 ASAP and report back...
Thanks for your time
Darin