Marshall TSL60 OT Primary resistance

[pdf64]

Possibly - it may go if you turn the presence one way or the other.
How about the output power; does it seem ok? What Vac can you get across the load?

[jstbrowsin]

sorry this is where my noobishness shines through. The readings you see was the amp unplugged with a signal generator 1k running through (that represents an AC wave right?). All leads unplugged from OT.

By Vac do you mean to plug it in and measure the AC voltage on the secondaries? I'm a little reluctant to stitch it all back together again and alot weary of the high b voltage.

Cheers
T.C

[pdf64]

The readings you see was the amp unplugged with a signal generator 1k running through

I see, so the scope pics were purely the OT, such that the OT plate leads were connected to the sig gen 'hot' and 'ground'?
If that's the case then oscillation wasn't causing the wave from the secondary to look funny.

I'm a little reluctant to stitch it all back together again and alot weary of the high b voltage

I take your point and sympathise!
From what we've got so far I'm just reluctant yet to condemn the OT.
It may be premature to recommend that you buy a replacement, though as Enzo points out, it is useful to have one available to sub in.
Does your tech buddy have anything suitable spare? If so can you wait for his return?

[jstbrowsin]

The signal gen ground was connected to the ground of the probe. Signal to primary and test to individual pins. Did I put the ground of the sig gen in the wrong place?

Thanks for hanging in there with me guys I really appreciate it. I just spoke to the tech at my polytech (I'm an adult student 47 years young ;-) ) at I'm taking it in to for further testing such as IR test etc. Stay tuned and fingers crossed. But then if thats ok I still have to find out what blew the fuse to begin with, oh well its fun anyhow I just wish I didn't have the pressure of this fridays gig it would be alot less harrowing eh.


Cheers
T.C

[g1]

Sorry, when you originally said it blew I didn't realize you meant the fuse. Was it the mains fuse? (not sure if this model has more than one)
Have you checked the screen resistors? Often when a power tube goes, it will blow the screen resistor. Then, even though you install good replacement tubes you will get low output.
Also, earlier you stated "I have just taken usual voltage readings with DMM and its all normal". You need to be more specific. What readings did you take and what did they measure.

[jstbrowsin]

Ok the verdict is in (via an Insulation Resistance tester). . . the OT is toast

So thanks to everyone who helped me here I really appreciate your time.

Now I ask the question again does anyone now what the primary resistance specs or where I could find them (please don't say google it cause I have googled it to death) would be for this OT.

Its a Dagnall D2504 from a TSL60.

Cheers
T.C

[jstbrowsin]

Never mind I just happened to ring a guy who had worked on one recently and he gave me all the specs I needed so I'm golden now. Synchronicity is a wonderful thing.

For future reference Marshall TSL60 Output Transformer Dagnall D2504:

Primary readings: W7 - W19 = 40Ω, W7-W17 = 40Ω

Secondary side: W6-W5 = 0.4Ω, W6-W4 = 0.6Ω, W6-W3 = 0,8Ω.

Colour codes for primary: W7 = Green, W19 = Blue and W17 = Purple
Colour codes for secondary: W6 = orange, W5 = Blue, W4 = Brown and W3 = Purple.

Now we have some google fodder for the TSL60

Thanks again guys for all your help.

Cheers
T.C

[jmaf]

Never mind I just happened to ring a guy who had worked on one recently and he gave me all the specs I needed so I'm golden now. Synchronicity is a wonderful thing.

For future reference Marshall TSL60 Output Transformer Dagnall D2504:

Primary readings: W7 - W19 = 40Ω, W7-W17 = 40Ω

Secondary side: W6-W5 = 0.4Ω, W6-W4 = 0.6Ω, W6-W3 = 0,8Ω.

Colour codes for primary: W7 = Green, W19 = Blue and W17 = Purple
Colour codes for secondary: W6 = orange, W5 = Blue, W4 = Brown and W3 = Purple.

Now we have some google fodder for the TSL60

Thanks again guys for all your help.

Cheers
T.C

Those are probably not the specs you want. What you should be looking at is primary and secondary impedances and OT power in Watts. The DCR is useful for some purposes but not for going out and buying a new OT.

[jstbrowsin]

thanks mate, those specs are the specs I was asked for to get the OT rewound not to buy a new one but I will keep that in mind should I need to buy one.

Cheers
T.C