RF Punch 200a4 nearly the same as 400a4?

[gisewhcs]

I have a bunch of RF PCBs sitting here, several in wrong sinks, so I had to look up who is who.

While looking up the PC-# in the RF-TechLib I noticed that PC-3084A is used in the 200a4 and obviously the 400a4.
(Or 300X and 500X depending on the year, from what I saw.)
There are just some other resistors in the PSU (feedback, setting the rail) and caps mentioned.
(And some in the audio input circuit, from what I read, but that's irrelevant in this moment.)

The most interesting point to me is, that the transformer has the same part number.

I looked at several pics, but I couldn't see any difference between the two transformers.

As I will have to recap that one, something fell on the PCB, cracked some mylar and el. caps, it would be a very easy mod.
Setting the rail higher, picking one of the the good sinks and I'm done.


Thanks for your help!

Julian

 

[AKHeathen]

interesting..... can you provide some more info? specifics? i'm getting one and will look at possibly doing this..

 

[gisewhcs]

I don't have more specific infos, that's why I'm asking for some.

Here is the schematic and the PCB-Layout:
Rockford Corporation Technical Library CD
Looking at the 400a4 (Rockford Corporation Technical Library CD) there are only the few resistors changed.

But I'm still unsure if the transformer is really the same in both amps.

 

[Perry Babin]

If the part number on the transformer is the same, they're almost certainly the same.

Do you have working boards for both the 200a4 and the 400a4?

 

[gisewhcs]

No I just have the "working" board from a 200a2/300X with the smashed caps on it.
It's really working! Even with some torn off caps!

I looked through the RF pile and found a 550x, rated the same as the 400a4, this one has a mechanical bigger transformer in it.

I just took a caliper and measured the 200a4 transformer.
Diameter: ~1.5''/3,7cm
Height: ~.5''/15mm

Does anybody have a 400a4 to measure the transformer?

 

[chipper]

I wonder the same but different model amps. Punch 360a2 = punch 401s. Very similar pcbs.

 

[gisewhcs]

I just zoomed in a 400a4 pic from Ampguts and held the 200a4 PCB next to my monitor...
From what I saw it may be really the same transformer.
I will harvest the needed parts from some of my donor-boards and give it a try.

And I will keep you updated!