I'm not following you guys - the schematic shows the T1 red / yel at gnd, and the other leg of the aux cap at the choke pads.
So you connect the ct to one of the pads, the gnd end of the aux cap to the other.
That outline drawing shows the same thing.
His looks right - or OK - to me.
Win W5JAG
So you connect the ct to one of the pads, the gnd end of the aux cap to the other.
That outline drawing shows the same thing.
His looks right - or OK - to me.
Win W5JAG
OK color me corrected!!! LOL
only thing i cant figure out is where he connects star ground to the board...i have mine at the terminal where the PT CT is.
only thing i cant figure out is where he connects star ground to the board...i have mine at the terminal where the PT CT is.
Yes that looks the same as he has to me.
That N/C between the 2 reds means not connected.
You told him to put the centre tap there.
He has the red/yellow ct up above where it belongs.
That N/C between the 2 reds means not connected.
You told him to put the centre tap there.
He has the red/yellow ct up above where it belongs.
Wiring
I would like to have the wiring neater. I'm loath to trim the wires before I put it in the Hammond 17x12x2 steel chassis.
The wires are: yellow 5 volt to rectifier T1, red to HV T2, SW1 red wires are tube/ss rectifier switch, T1red yellow is per George's instruction picture( is that a good defense?)with supplemental cap, L1 is supplemental cap and choke.
C1 and 2 are/were 🙂 rated 500 volts.
I guess I am cheap with my solder. All joints do go through the board.
Is everything in the right placeR17 and 27 were placed on bottom because they would not leave enough space when mounted on top to have board mounted with sockets level with chassis face.
I would like to have the wiring neater. I'm loath to trim the wires before I put it in the Hammond 17x12x2 steel chassis.
The wires are: yellow 5 volt to rectifier T1, red to HV T2, SW1 red wires are tube/ss rectifier switch, T1red yellow is per George's instruction picture( is that a good defense?)with supplemental cap, L1 is supplemental cap and choke.
C1 and 2 are/were 🙂 rated 500 volts.
I guess I am cheap with my solder. All joints do go through the board.
Is everything in the right placeR17 and 27 were placed on bottom because they would not leave enough space when mounted on top to have board mounted with sockets level with chassis face.
It really does seem that your voltages are just too high for your meter (and your caps).
If you can bring it down to start with by following W5jag's advice and that's ok, then you can look at the heater voltages.
They can read differently how you read them depending on whether you use the elevated ground or not.
If you can bring it down to start with by following W5jag's advice and that's ok, then you can look at the heater voltages.
They can read differently how you read them depending on whether you use the elevated ground or not.
I am not well versed in electrical workings. I will move C1 to C2. (They are both rated at 500 volts, but if it works, okay)
I need to order a new C2. What should I order? Or is that tbd?
Did I make an error in caps for the 6k7cg?
I need to order a new C2. What should I order? Or is that tbd?
Did I make an error in caps for the 6k7cg?
Your line voltage looks high to me - but inexpensive meters like that may not have good accuracy on AC voltages.
That transformer is marked 117V. If your line is 124 volts, it will be putting out more than its rated voltage. I don't have any Hammond power transformers, but from what I read, they are notorious for putting out higher voltages than specified.
You may have the bad combination of a high line voltage, and transformer that puts out more voltage than it should.
I would just try to fix one problem at a time.
Win W5JAG
That transformer is marked 117V. If your line is 124 volts, it will be putting out more than its rated voltage. I don't have any Hammond power transformers, but from what I read, they are notorious for putting out higher voltages than specified.
You may have the bad combination of a high line voltage, and transformer that puts out more voltage than it should.
I would just try to fix one problem at a time.
Win W5JAG
Take 2
I removed lazy C2 and replaced with C1.
Rewired board paying very close attention to which wire where. Checked grounding.
Plugged amp in again. Powered up.
I measured V2, rectifier. Pin 1. Zero
V2 Pin 2 200 scale 1 on left of screen changed to 500 screen. Shows 846.
Switched to a allsun EM830 multimeter, 600 vac. It showed 846 also.
Then measured T1 yellow connection. Also shows 846 there.
I stopped.
If meters are correct, it will cook new C2 also?
As an aside- at L1, does it matter which of two connections choke and supplemental cap go?
I removed lazy C2 and replaced with C1.
Rewired board paying very close attention to which wire where. Checked grounding.
Plugged amp in again. Powered up.
I measured V2, rectifier. Pin 1. Zero
V2 Pin 2 200 scale 1 on left of screen changed to 500 screen. Shows 846.
Switched to a allsun EM830 multimeter, 600 vac. It showed 846 also.
Then measured T1 yellow connection. Also shows 846 there.
I stopped.
If meters are correct, it will cook new C2 also?
As an aside- at L1, does it matter which of two connections choke and supplemental cap go?
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I think that you need to get another meter that handles 1000v or thereabouts. The only explanation that I can see is that that meter works ok up to 500v and then goes bonkers. I'm not an expert, I built an SSE last year so I'm at the same level as you Lee but mine just worked although it is much more of a mess than yours. Your voltages are bordering on 500v so you need a meter that reads higher. Imo.
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Sent from my SM-G930F using Tapatalk
Something that puzzles me is these are readings from the tube heaters (?).
Supposed to be 5 volts. Right?
Supposed to be 5 volts. Right?
Your objective and methodology are confusing to me, but I am easily confused.
Are you trying to measure the AC voltage at the rectifier heater pins with the rectifer tube in place? I don't think a cheap meter will accurately measure AC in the presence of a large amount of DC. The typical way to do this would be to use a blocking capacitor to keep all of the DC out of the meter. That, after all, is the purpose of a capacitor - to block DC and pass AC.
The easier way to do it is to remove the rectifier tube, set the meter to AC, and then measure it.
To measure DC - set the meter to DC. You can't read DC accurately with the meter set to AC.
Maybe I am misunderstanding what you are doing and how you are trying to do it.
Win W5JAG
Are you trying to measure the AC voltage at the rectifier heater pins with the rectifer tube in place? I don't think a cheap meter will accurately measure AC in the presence of a large amount of DC. The typical way to do this would be to use a blocking capacitor to keep all of the DC out of the meter. That, after all, is the purpose of a capacitor - to block DC and pass AC.
The easier way to do it is to remove the rectifier tube, set the meter to AC, and then measure it.
To measure DC - set the meter to DC. You can't read DC accurately with the meter set to AC.
Maybe I am misunderstanding what you are doing and how you are trying to do it.
Win W5JAG
Yes...the 6k7vg will do 350vac and ultimately 493vdc. I suspect issues with his measuring technique or equipment.
So far I haven' done anything with tubes except try 12at7 in its socket. The measurements are all without tubes.
I was using Ty's "for dummies" . The measurements on the rectifier socket pins 4 and 6 to me seemed reasonable at 423, however, at pin two, and T1 yellow look wat too high. Originally showing 14xx. Those should be 5 volts.
And C2 was lazy and quit.😀
I removed lazy cap and replaced with old C1.
Now T1 yellow pin 2 are showing 8xx.
Rather than have anything else blow I stopped.
Is measuring outputs of transformer next move? I am ignorant of what to do. To me it seems a transformer problem.
Thank you for help, all of you!
I was using Ty's "for dummies" . The measurements on the rectifier socket pins 4 and 6 to me seemed reasonable at 423, however, at pin two, and T1 yellow look wat too high. Originally showing 14xx. Those should be 5 volts.
And C2 was lazy and quit.😀
I removed lazy cap and replaced with old C1.
Now T1 yellow pin 2 are showing 8xx.
Rather than have anything else blow I stopped.
Is measuring outputs of transformer next move? I am ignorant of what to do. To me it seems a transformer problem.
Thank you for help, all of you!
Look at the schematic that was posted.
Did I see diodes for the solid state rectifier option in your earlier picture? And do I see some kind of switching for these? Do you know if those diodes are switched in or out of circuit while you are taking these measurements? I would look real hard at that.
I would put my money on that before I would suspect a transformer problem. It's ( almost ) always the simple stuff that gives you Hades.
Win W5JAG
Right now I have switch to tube rectifier.
When I started Ty's test procedure for power I started at the rectifier socket which showed zero, and I changed switch to tube.
And then you have been in on what happened.😀
When I started Ty's test procedure for power I started at the rectifier socket which showed zero, and I changed switch to tube.
And then you have been in on what happened.😀