Plexi visio layout?

[jelle]

Hi,

Does any of us have a visio layout of a plexi amp?

Thanks!

jelle

[selloutrr]

will this work? which model # are you looking for?

[KT66]

Do you have Visio ? Because I have a layout for a Hiwatt linked input in a small box plexi chassis that could be turned into a Plexi without too much trouble. In fact, I'll just do that myself - I'll have it posted within the next day.

[jelle]

Selloutrr,

Thanks. Did you upload a PDF of a .vsd file? I'm specifically looking for a .vsd file.

KT66, that would be great. I can convert it myself too. Thanks!

Jelle

[Structo]

Which model Plexi are you looking for Jelle?

I have a few PDF files with layouts of various Marshalls that can be converted.

[jelle]

plain 1959 late 60's or early 70's works for me .

Alternatively 50W would be cool too.

BTW, how do you convert them?

Thanks!

Jelle

[KT66]

Took me a little longer than I thought It would to do this. Hope it's helpful to you in some way. It's not a layout of a particular plexi amp, but kind of a hodgepodge of elements that appear in different plexi varieties. I put the .68 2nd stage cathode cap in even though I believe that's a metal face era feature - I usually add it on a switch when I build this circuit. Some of the leads are shorter than the vintage layout ( like on the first 2 valves cathodes) because modern resistors are too short to go all the way across a 3.125 inch board. This will be an issue with the feedback resistor as well if you don't move the tube-side-of-the-board turret closer or extend the resistor's leads by soldering a piece of wire to it. The grounding scheme is not the same as the vintage either, but is a 2 point star that I know works better than the vintage. The outside foil band is in the correct position for all signal caps I think, but if anybody thinks otherwise please let me know so I can fix it. If you would like me to change something on it just let me know.

Happy building.

P.S. I tried to post the Visio file as well, but it seems that format is not allowed. Is there some way to do that that I am missing ? I can email it to you if you want, just let me know.

[M Fowler]

Ryan that was a nice PDF layout thanks for loading that. I converted that to visio.

I did get back to Jelle with some different visio layouts.

I tried to upload the visio layouts here but no go, sorry.

Mark

[jelle]

Thanks guys, you both have been a great help.

Jelle

[marcoloco961]

Took me a little longer than I thought It would to do this. Hope it's helpful to you in some way. It's not a layout of a particular plexi amp, but kind of a hodgepodge of elements that appear in different plexi varieties. I put the .68 2nd stage cathode cap in even though I believe that's a metal face era feature - I usually add it on a switch when I build this circuit. Some of the leads are shorter than the vintage layout ( like on the first 2 valves cathodes) because modern resistors are too short to go all the way across a 3.125 inch board. This will be an issue with the feedback resistor as well if you don't move the tube-side-of-the-board turret closer or extend the resistor's leads by soldering a piece of wire to it. The grounding scheme is not the same as the vintage either, but is a 2 point star that I know works better than the vintage. The outside foil band is in the correct position for all signal caps I think, but if anybody thinks otherwise please let me know so I can fix it. If you would like me to change something on it just let me know.

Happy building.

P.S. I tried to post the Visio file as well, but it seems that format is not allowed. Is there some way to do that that I am missing ? I can email it to you if you want, just let me know.

Nice layout. Just a note to the designer. Your 100k feedback resistor doesn't show which tap of the OT it connects to. Would that be the 8Ohm contact for this amp?? Not trying to nitpick, just an observation as I was checking out the circuit.

[KT66]

Crap, I missed that. Yes 8 Ohm tap, thanks for spotting that ( I'll fix it and upload it again after I post this). Although, like I stated it's kind of a hodgepodge DIY layout, and that's one part that varies a bit between models. One reason that a PPIMV sounds so good in this circuit is because of the reduced negative feedback you get at low master settings, so it's a good part ( the NFB resistor ) to tweak to taste, although of course less NFB = less effectiveness with the presence control.

Thanks for the compliment Mark - I love Visio because even a hack like me can make something that looks good, but I still haven't mastered all of the features. How do you convert from a PDF to Visio ? I fiddled with it a bit after I read your post but couldn't figure it out.

Plexis don't seem to get discussed around here much, I guess there are better forums for that. I was reading an interesting article at Merlin's site about DC coupled cathode followers that those interested in the circuit, and Marshalls in general might find interesting :

http://www.freewebs.com/valvewizard1/dccf.htm

[M Fowler]

I open the .pdf with Coral Draw X5 save that as a .svg (scalable vector graphic). Once that is done I open it with Visio and save it.

Mark

[Allynmey]

you should be able to upload vsd files now.

[M Fowler]

Deleted not able to load.

[Allynmey]

all set