1955 Tweed Deluxe ...need some help please

[Chris G]

Hi All,
So I was cleaning up a few caps (shortened them.. nothing major)....Power up the amp and we have problems...
Rec. lights up voltage present. No pilot, no filaments, ....no voltage drop at all..500+ volts straight down the line.... at every spot, the heaters and pilot not lighting is freaking me out a bit....Tried new rec. tube, no tubes, power tubes....
Any ideas???
Thanks
Chris

[Leo_Gnardo]

Check for a broken solder connection on the filament line - after you drain the hi voltage from those filter caps.

[martin manning]

No power to the 6.3V filaments. Check at the PT leads. If nothing there then the winding is open.

[ToneMerc]

Hi All,
So I was cleaning up a few caps (shortened them.. nothing major)....

What exactly did you do and to which caps, obviously there's major problems now. Also, "500V down the line" isn't telling me much. At what exact points to you have 500V volts?

TM

[Chris G]

Hi All,
So I was cleaning up a few caps (shortened them.. nothing major)....

What exactly did you do and to which caps, obviously there's major problems now. Also, "500V down the line" isn't telling me much. At what exact points to you have 500V volts?

TM

The previous owner did a quick cap job, snipped the old ones out and tacked new ones in at 4 spots, the 2 preamp bypass caps, the bias bypass cap, 1st filter... all I did was shorten the leads to get them closer to the board, neat...I have 500 + volts at every B+ node...with tubes in or tubes out. new tubes, old tubes.

[Firestorm]

No filament current means all your tubes are "off." No current flowing means no voltage drop. Do what Leo and Martin said.

[Chris G]

Thank-you for the tips guy's.. 6.3 volts A.C. is present across the PT leads. This model has 1 side of the filament to ground.

[martin manning]

Thank-you for the tips guy's.. 6.3 volts A.C. is present across the PT leads. This model has 1 side of the filament to ground.

And one filament pin on each socket grounded locally? Must be a broken/bad joint between the PT lead connection to the first tube socket or the other lead's connection to ground.

[Richie]

Like others are saying, if all the other tubes are not lighting up[except recto is ok], then you have a bad connection if you can measure the voltage. If you can measure the voltage at the tube pin,and the tube is not lighting up, then the socket is bad, or dirty, or the tube is bad.
Also pull the tubes measure at each tube pin heater connection.

When you get the tubes to light up,and start working, the high B+ should fall to the correct voltage at each plate supply node/tube plate etc.

[Chris G]

Like others are saying, if all the other tubes are not lighting up[except recto is ok], then you have a bad connection if you can measure the voltage. If you can measure the voltage at the tube pin,and the tube is not lighting up, then the socket is bad, or dirty, or the tube is bad.
Also pull the tubes measure at each tube pin heater connection.

When you get the tubes to light up,and start working, the high B+ should fall to the correct voltage at each plate supply node/tube plate etc.

Thank-you ALL!!!! I have checked each part of the Transformer, it all checks out ..I have buzzed out each connection along the string both ground and the voltage side.....My focus has been on the 1st power tube socket, Checked the tension, cleaned it out really good, nothing...I am going to re-solder the heaters maybe that will help...Thank-u all so much!!!!

[Chris G]

Blown/ intermittent 6.3 volt winding, it reads good out of the circuit, when you hook it up nothing...tacked in a filament transformer and it light's right up.
Thank-you all for the help!!!!

[Leo_Gnardo]

Blown/ intermittent 6.3 volt winding, it reads good out of the circuit, when you hook it up nothing...tacked in a filament transformer and it light's right up.
Thank-you all for the help!!!!

OW what a bummer. Well at least you know what it is. On rare occasions I've managed to dissect a dodgy transformer, find and mend a bad connexion where the lead-out wire is soldered to the winding wire. On an antique collectible, it's worth a try.

[Chris G]

Blown/ intermittent 6.3 volt winding, it reads good out of the circuit, when you hook it up nothing...tacked in a filament transformer and it light's right up.
Thank-you all for the help!!!!

OW what a bummer. Well at least you know what it is. On rare occasions I've managed to dissect a dodgy transformer, find and mend a bad connexion where the lead-out wire is soldered to the winding wire. On an antique collectible, it's worth a try.

Hi Leo,
That is an option the owner is thinking about, can't hurt at this point...but will see what he wants to do.
Thank-you!!!
Chris