Pro Jr. Layout?

[Jazz P Bass]

I really think the OP should print this out and present it to his friend.

ProJuniorIII_schematic_Rev-F.pdf

The pcb IS the whole amp.

To make it point to point you will need a tag board for at least the power supply.

Add to that you will have to source the tube sockets.
Also the front panel controls are pcb mounted. So they will have to be purchased.
(the pots & the jack)

In the end you will have most of the components swinging in the breeze as you will probably have to use the socket pins for attachment points.
Add to that all of the wire to connect things.

Waste of time is what your friend wants from you.

[jrdamien]

I really think the OP should print this out and present it to his friend.

[ATTACH]43572[/ATTACH]

The pcb IS the whole amp.

To make it point to point you will need a tag board for at least the power supply.

Add to that you will have to source the tube sockets.
Also the front panel controls are pcb mounted. So they will have to be purchased.
(the pots & the jack)

In the end you will have most of the components swinging in the breeze as you will probably have to use the socket pins for attachment points.
Add to that all of the wire to connect things.

Waste of time is what your friend wants from you.

There's either a miscommunication taking place (it IS the internet) or people aren't reading this forum thoroughly. Or...well, I don't know why there'd be this much unsolicited condescension.

I have the schematic. I have the PCB "layout." I was looking for a ptp layout. Why I need it or whether it'd be a waste of time or money was never a question or concern.

Yes, to build an amp from scratch you need to buy all the things needed to build an amp from scratch. That's the whole idea.

[g1]

No offence intended and just to be clear, there was never such an animal in production? Or was there a custom shop PTP version?
If not, you are looking for someone who has done a conversion, or scratch build of Pro Jr. and is willing to share their layout?

[Justin Thomas]

Okay, maybe I can help. I don't know if the "scale" of the innards - trace spacing, etc. - will allow this. But here's what I did with my Prosonic's rectifier switch board. The switch broke, and so I had to replace it. Being a 12-pin switch, mounted on a tiny PCB, I removed the PCB from the switch, carefully. Yes, traces had come up. I folded them back in place, and it was a double-sided board.

I took pictures from every angle of that little board. Then I drew a picture of it, to scale, showing where the traces were on both sides. Next, I sanded both sides of the PCB, so that there were no more traces. I drilled out the 12 holes for the switch and put a turret in each. Then I mounted the new switch on the backside of the turrets and soldered the pins in. The switch was mounted on what would have been the underside of a traditional board. On the turret side, I ran the hookup wires as the traces had been.

As far as making a turret board OUT OF a PCB, that would depend on the quality and thickness of the PCB material, and whether or not the traces are widely enough spaced to allow for turrets or eyelets. I don't know if a Pro Junior would allow it, but I could do it with an older Ampeg or Marshall from the 70s. But yes, it is POSSIBLE to make a layout, especially since turrets can have connections on both sides.

That said, I bet that any old late-50s Tweed Fender layout with two preamp & 2 power tubes would be close enough. Yes, you'd absolutely have to adapt your pots, switches, etc. to fit, but the layout itself isn't that hard. And the reason nobody has one MAY be because nobody has had the need to MAKE one. Question: IS THIS A SCRATCH BUILD, as in, you're building a clone, OR are you gutting a perfectly good PJ to cram a PTP circuit in it? If the former, yes, be a pioneer and make a layout from the schematic! Otherwise, don't gut a perfectly good amp until it flames out irreparably.

Just my opinions,

Justin

Justin

[nosaj]

?????????????????????????????
Of course you need a layout, you canīt randomly throw a bucketful of parts inside a chassis and solder them where they fall or plain *try* to interconnect them without further thought.

I used to build guitar amps on terminal strips before using eyeletted or printed boards and had to spend a good afternoon or two with pencil, paper and a good eraser to layout what I was about to build.
And if you need to build more than one unit, you need a layout for consistency and repeatability, because "thereīs more than one way to skin a cat".

When I built the champ and the kalamazoo one, and the watts dominator I tied off tube sockets and pots. My layout was the schematic, Which is why I said with a true point to point a layout is not required just a few rules regarding lead dress.

nosaj

[Jazz P Bass]

The op wants a layout.

None exists.

Guess you are on your own.

Edit: please take all posts with a grain of salt.
I do not see any particular post that contained "unsolicited condescension."
More in fact, most are intended (in my mind) as a 'sanity check'.
PtoP from scratch can be a noble, if very time consuming, effort.
In this case, as no actual physical layout exists, the ball is in your court to be the first to post one.

[Justin Thomas]

I think most of the confusion here is whether we are gutting a Fender Pro Junior and putting PTP guts in it, or if we are simply building a CLONE of a PJ in a new cabinet, chassis, etc. The sanity check is, please don't gut a perfectly god amp. Otherwise, yes, pioneer a layout.

Which then begs the question: are we talking <TRUE> PTP, or what is commonly CALLED "PTP"??? If you are wanting an eyelet or turret board, tyhen I agree - any small Fender tweed or maybe a brown Deluxe layout would help, <IF> you can adapt it to a PJ chassis. Personally, I build true PTP as much as possible, one at a time, in different chassis. As such, no, I do not use layouts. Now, if you are Matchless, yes, a layout CAN be drawn, UPON SUCCESSFUL COMPLETION OF A WORKING AMP. Again, as others have said, you are on your own.

Justin

[vintagekiki]

The op wants a layout.

None exists.

What he wants ("Under the Hood" PCB layout) is part of the factory's production line documentation.

With the attached schematic and the layout of the components, with little effort and the corresponding PCB Design Software, PCBs can be designed and manufactured

Another variant is to dismantle the PCB from the amplifier and photocopy it.

[Enzo]

But he has no interest in a pcb, in post #3 he told us, he has a customer who wants him to build a ptp wired Pro Junior. He doesn;t have an existing amp.

As I read it, he is hoping someone has already done this, and he would like such a person to provide a layout.

[g1]

Thanks for the reminder of the intent Enzo.
Better searching will be had from looking for 'Pro Junior build'.
Such as these:
Hoffman Pro Jr Turret board
Tweaking my Pro Jr rewire.
Pro Junior Conversions - s2 Audio Technology Photo Gallery - Powered by Phanfare

[J M Fahey]

Just thinking aloud:

1) just checked the Pro Jr schematic.
Itīs a simple amp, single channel, no FX loops, no reverb, not even a tone stack.

2) Itīs very doable either as true PTP (terminal strips) , eyeletted board or turrets, so choose one and do it.
No, it wonīt be perfect on first try, thatīs why the third design element I suggested was an eraser.

You can reach an acceptable layout in an idle afternoon, then let it rest 1 or 2 days and go over it again, youīll find some details you hadnīt noticed.
Then build it.

If you wish, you may later share it here.

[mozz]

I do these all the time, scratch builds. Just get your board and start building it. I love challenges. I do have a pro junior here i got cheap and eventually it will be built with one of these. Just finished 2 AO-35 Hammonds into a spitfire and carmen ghia and a filmosound build. Just lay it all out through the eyelets before you solder. Ali express has these boards cheap.

[jrdamien]

Worked out today over at el34.

[minim]

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