Lindell PEX500 parts request

[mylesgm]

I’ve got a sick PEX500 with a dead input transformer. Anybody know what the specs of the LXI-046 transformer is? Lindell are not forthcoming with info as yet and I’d live to repair it. It’s a basic solid state pultec clone but I don’t have a schematic.

 

[TwentyTrees]

If you're not able to find any info on the specific transformer, you may be able to at least work out the ratio. From the user manual, the input impedance is 10k; and the characteristic impedance of the filter circuit will tell you what the filter expects from the secondary. For example, if filter RLC values are the same as they would be in a Pultec then it would likely be 10k:600 on the input. Of course, this is assuming it's the same topology as a Pultec, and the input transformer directly feeds the filter section (I'm assuming it is, as pictures suggest only one op amp).

Good luck!

 

[Rob Flinn]

Is it not possible to request this information from Lindell ?

 

[mylesgm]

Is it not possible to request this information from Lindell ?

Have requested from Lindell, no information of any kind is forthcoming and having had to interact with them before I’m not holding out much hope there.

 

[mylesgm]

If you're not able to find any info on the specific transformer, you may be able to at least work out the ratio. From the user manual, the input impedance is 10k; and the characteristic impedance of the filter circuit will tell you what the filter expects from the secondary. For example, if filter RLC values are the same as they would be in a Pultec then it would likely be 10k:600 on the input. Of course, this is assuming it's the same topology as a Pultec, and the input transformer directly feeds the filter section (I'm assuming it is, as pictures suggest only one op amp).

Good luck!

Thanks, I’ll explore that. I have quite a few tx here with varying ratios so we’ll see.

 

[TwentyTrees]

Thanks, I’ll explore that. I have quite a few tx here with varying ratios so we’ll see.

If there's a difference in level between unity vs the unit with another input transformer inline, that will also tell you something about the ratio you're looking at.

 

[igs]

Hey, I designed this module for Lindell a long time ago. If I remember well, this input transformer is a custom-made OEP. I think it's a VTB9046 substitute. Here's a footprint picture.

 

[mylesgm]

Hey, I designed this module for Lindell a long time ago. If I remember well, this input transformer is a custom-made OEP. I think it's a VTB9046 substitute. Here's a footprint picture.

Thanks!!

 

[mylesgm]

Hey, I designed this module for Lindell a long time ago. If I remember well, this input transformer is a custom-made OEP. I think it's a VTB9046 substitute. Here's a footprint picture.

So is it likely to be setup as 10k input, 600ohm output?