Rogers to Marshall Conversion

[Jack1962]

I recently bought a Rogers model 1055 all tube reel to reel for $10 at a local thrift store. What I am waning to do is convert it into a mini marshall  does anyone here have a schematic for this thing?
also I have a question: can I take 2 output xforms on a single ended amp and tie the primary's together and use it as a center tap xformer for a push pull output?


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[Jack1962]

I'm sorry this is a Roberts model 1055

[stingray_65]

I recently bought a Rogers model 1055 all tube reel to reel for $10 at a local thrift store. What I am waning to do is convert it into a mini marshall  does anyone here have a schematic for this thing?
also I have a question: can I take 2 output xforms on a single ended amp and tie the primary's together and use it as a center tap xformer for a push pull output?


                                                         Rock On

in short, no.

the cores will not be saturated correctly. It may work technically, but I would feel safe in saying it would sound lousy.

I can think of several ways I might go about the conversion.

I'm guessing at this point, but I think you are considering going the low dough route, using as many of the old components as possible.

The way I think these through is to start with the PT.

Fully measure your PT. Disconnect all of your leads, measure their outputs and draw it out on your blueprint. This will basically determine the rest of your amp. A lot of these old recorders have no PT's and the heaters are line powered and run on relatively low B+ that are just rectified mains voltages. For safety's sake don't go this route.

Next is to decide on your OT. the iron you have is already matched to your power tubes, that is the simplest way to go, but probably, from your post, not the way you want it to go.

so decided which output tubes you want to use and find the correct OT to match your choice of finals with the limits of what the PT is capable of delivering.

After you have this info, it would be simple to draw up a schematic with the same topology of your choice of amps.

To go any further right now is pointless without knowing the parameters we're working with. a schematic of the tape recorder is not very necessary at all as you'll likely be changing most everything to get what you described in your OP.

SO, if you can, post the tube compliment of the entire unit, this we can use to deduce the power capability of the PT (mA's) then post the unloaded voltages of the secondary side of the PT.

Like I said their are many ways to go about what you want to do, this is just a few thoughts on how I would go about designing this

Ray