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i picked up this Motorola console pull today for $25 bux....so far i have determined the Midwest Coil power transformer works, so i know it wasn't a total wash. its a 6v6 push pull, should make a nice Fender Deluxe clone

ok first question, i am embarrassed to not know this yet, but regarding the PT secondaries: you can see in the pic i have labeled the high voltage leads. last night i determined that when i input 10VAC on the primary:

wire A + B= 32V
wire A + C= 32V
wire B + C= 64V

so i am confused about the color coding, although the "striped" wires are similar, i guess the cloth weave is not identical. but do my measurements indicate that wire A is the center tap? i got the other wires all sorted out

Yes - your measurements indicate that A is the centre tap.

Are you sure about it being a 6V6 push pull. I only ask coz in the pic you posted the tubes look more 6L6'ish.

Good score either way and will convert to a nice Fender Clone either way.

Cheers,
Ian

thanks for clearing that up.
aren't the wire colors a bit odd...?
yes those are 6v6GT, branded "Motorola, Made In USA"...also a 5y3, pair of 12au7, and a 6au6

For a Fender Deluxe clone (I've built them in the past), the 6AU6 will have no function, and the 12AU7s should be replaced with 12AX7s, or use a 5751 and a 12AX7, and it would be a simple matter to add in a reverb and / or a tremolo into the amplifier circuitry.

There were a lot of "non-standard" transformer lead color codes out there, in the old days (and there still are, today, just look at the Edcors)

/ed B

there were quite a few different iterations of the Deluxe...i think the 5E3, which is supposed to be the "best", calls for a 12ay7 @ v1, and an AX7 as PI. i ended up breaking a preamp tube socket during desolder(they were very liberal with solder on those old amps) so i had to scrounge a couple up, get those mounted...then i nipped out a hole for an IEC connector, drilled for switches/jacks/pilot/fuse.....so hopefully the nasty work is mostly done

If the tube sockets are in good shape, then by al lmeans re-use them. I generally strip old chassis like this all the way down, and then save only the chassis and transformers, and replace absolutely everything else. The riveted-in tube sockets can be a pain to deal with, but the rivets can be easily drilled out, if necessary.

The different input tubes (12AX7, 12AY7, 5751, etc) can, and wil,l affect the amp's overall tonal qualities, just try rolling in different types and discover which one gives you the best sound and tone.

I'll have to take another peek inside my Tweed clone, IIRC, I settled on a NOS 12AY7 which I had on hand.

/ed B

the Fender 5e3 schematic calls for 1M pots for tone and volume.....on most Marshall amps, i think the pots are 500K.
whats the difference(besides half a meg!)?

The Fender and Marshall circuits have somewhat different frequency responses for their tone stacks, which deliver each amp manufacturer's own "unique" tone and "flavor", (Ameriican vs British) most of which is just a matter of the layer's personal taste, you could also experiment with the tone stack cap values, as well.

Combine those with the guitar's pickup selectors and tone controls, and the overall tonal qualities can have quite a wide range. Then combine those with the wide variety of guitara amp speakers' qualities, and the permutations become nearly infinite

The other main reason for the differences is to avoid any design infringement problems, of one manufacturer claiming that the other "stole" their design ideas.

/ed B

yeah i'm not worried about faithfully recreating a Fender Deluxe TM amp....i just want a functioning 6v6 pp to mess with. cool thing is, this chassis even came with 3 pots, just like a Deluxe....but i have not measured the values yet