"Promiscuous Girlfriend" So many types of dirty with 5840 Submini Pentodes

[Berger]

I have one of those transformers..but haven't used it yet. I believe it has taps to match the reverb transformer used in the murder one amp.

Hopefully I can test it tonight and let you know.

-Berger

[frequencycentral]

For anyone who does plan to build this pedal, be aware that the 3PDT wiring really does need to be the input-grounded-when-bypassed type. I've had to change my 3PDT wiring from how it is in the photos to combat high frequency oscillation when the effect is bypassed with the gain is above 1 o'clock.

[Berger]

fyi I tried the one I bought last night with my murder one and it worked fine. So i'll probably have to get some more at some point in time.

-Berger

I just came across these on Ebay and was thinking of buying one as an output transformer. Sounds pretty versatile and I don't think I'd ever try to build something greater than 10W.

http://cgi.ebay.com/Tube-amp-10-15-watt-output-transformer-6L6-6V6-6BQ5-etc_W0QQitemZ390069236209QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item5ad1f031f1&_trksid=p3911.c0.m14&_trkparms=65:12|66:1|39:1|72:1205|293:2|294:25

Seems like a good deal and I'd definitely buy one if I just knew whether they would work for these kinds of projects or not for sure. I know the seller is good because I just received a 6112 from him today. I really need to finish these papers and get to experimentin'!

[Toney]

 For those that Vero....

http://www.aronnelson.com/gallery/main.php/v/Toneys-Album/Prom+Girl.gif.html?g2_imageViewsIndex=1

NOTE: This was done late at night last weekend, so please check it against the schem in this thread and report any errors or improvements.

 

[doitle]

I ordered two 70 Volt Line Transformers off Ebay. Maybe I can figure out how to use one as an output for this or a similar submini amp. I'm so excited to get home and open my package and get experimentin'!

[frequencycentral]

I ordered two 70 Volt Line Transformers off Ebay. Maybe I can figure out how to use one as an output for this or a similar submini amp. I'm so excited to get home and open my package and get experimentin'!

Hmmm, well this is a pedal not an amp, but it could easliy become an amp with a bit of a redesign I guess.

[doitle]

I ordered two 70 Volt Line Transformers off Ebay. Maybe I can figure out how to use one as an output for this or a similar submini amp. I'm so excited to get home and open my package and get experimentin'!

Hmmm, well this is a pedal not an amp, but it could easliy become an amp with a bit of a redesign I guess.

Yeah I meant in relation to the Murder One. I realize that might be a little confusing since the thread is for the PG but me and Berger were sort of Off Topic'ing about the MO.

[juansolo]

I made a PG based on Toney's vero but found it wasn't quite right. It seems it was based on an early schematic that was corrected but the vero didn't follow suit (probably why the link is dead now). Anyhow after having a super-helpful chat with Rick he sorted out where the probs were and we bodged around it. I've just fettled the vero in PhotoShop so it's a bit bodged. The wire link to C8 with the cut before it was one of the fixes we had to do. Rick says this is just for some power filtering and should really go right on the front of things so it's probably best to shift that to row 1 of the board (or the socket itself) and just run it straight to ground. As I'd already built it, I just bodged a wire in as per the diagram.

As it stands though, this puppy is now verified!



It's fapping loud and really very sweet. More people should build this!





Almost forgot, I took a pic of the board after I bodged it:

[juansolo]

damn you do nice work FC !


those tubes look like missiles ... they aren't perchance the ones that were actually used for missile guiadance are they?

The ones I used were 

Well they're military spec ones at least... Mullard CV4501

...ok so they were used in radios 

[juansolo]

http://www.tubecollector.org/cv4501.htm

Missiles it is!

[Cliff Schecht]

For anyone who does plan to build this pedal, be aware that the 3PDT wiring really does need to be the input-grounded-when-bypassed type. I've had to change my 3PDT wiring from how it is in the photos to combat high frequency oscillation when the effect is bypassed with the gain is above 1 o'clock.

Perhaps grid stopper resistors would help to tame your oscillation problems. I've noticed that a lot of people don't use this resistor but you're using tubes that is meant to operate at up to 400 MHz. The article here shows you how to calculate the resistance needed based off of the tube you have (it's a simple 1/(2piRC) thing).

[frequencycentral]

For anyone who does plan to build this pedal, be aware that the 3PDT wiring really does need to be the input-grounded-when-bypassed type. I've had to change my 3PDT wiring from how it is in the photos to combat high frequency oscillation when the effect is bypassed with the gain is above 1 o'clock.

Perhaps grid stopper resistors would help to tame your oscillation problems. I've noticed that a lot of people don't use this resistor but you're using tubes that is meant to operate at up to 400 MHz. The article here shows you how to calculate the resistance needed based off of the tube you have (it's a simple 1/(2piRC) thing).

The oscillation is completely negated by the input-grounded-when-bypassed 3PDT wiring, but yes you are right, I need to do some more delving into the mathematics which underlies electonics. Thanks for the link.

[criszou]

Hi, I'm sure John Lyons would be more than happy to provide a PCB for you. But give it a week, as I'm in the middle of my build and need to confirm that my layout is bug-free before John makes up any PCBs.

I've already had to move C2, C9 and C14 to different locations on my perfboard to make room for the output socket - this would only matter if you plan to box it up the same way I have. I'll update the layouts anyway sometime this week.

How is the PCB? Is it bug-free? I don't have a luck with perfboard. Is there no problem if I build using the PCB, Rick??
Thank you

hey, why you don't design a head cab??? ^^

Cris

[frequencycentral]

How is the PCB? Is it bug-free? I don't have a luck with perfboard. Is there no problem if I build using the PCB, Rick??

I built mine on perf. I based the PCB layout on my perf layout. The perf layout is verified. If you check the PCB layout very carefully against the perf layout they should be identical. But please do check before you build, I'm only human, I make mistakes.

hey, why you don't design a head cab??? ^^

http://www.diystompboxes.com/smfforum/index.php?topic=73222.0
http://www.diystompboxes.com/smfforum/index.php?topic=74786.0
http://www.diystompboxes.com/smfforum/index.php?topic=78302.0

[criszou]

hi, frequencycentral
I see your guts picture. What is green resistor type? it is holco or what? and the blues capacitors? double layer ceramic? what mojo you you for elco and blue capacitors?

Thank you

[Dr Jones]

Rick,

Can you please specify the power rating on the resistors?  I'm guessing they're 1/2 watt, but the green ones look like they might be bigger.

Dr Jones

[frequencycentral]

Hi, all the resistors are 1/4 watt, the green ones are just 'recycled' from old equipment.  

[tgorman]

Rick you asked to see it so here it is my build of your Promiscuous Girlfriend. Just a great overdrive pedal. This was my first non-kit build, and it actually worked!



I took the liberty of coming up with my own name, I hope you don't mind.


Bit of a mess in here but it works.

[Strategy]

Sorry to bump an older thread but I'm just getting into the more final stages of building this. Before beginning my wiring I realized I'd started to solder in my MAX1044 in the wrong direction. So time to check my work and ask the "there's no such thing as a stupid question" questions. This is my first tube project as well so I'm doing some new things here.

- Is there a way to confirm the pinout of the tube? the bigger 'gap' between pins I assume is the gap between pin 1 and pin 8. Pin 1 should go to square pad on the pcb, correct? so if viewed from the top, the tube's pin 1 faces towards the 'southwest' corner of the circuit board? I'd hate to get this far only to learn I'd installed the tubes wrongly just because the polarity is hard to discern.

- Are the pots in the project PDF viewed as if from the front or from the back?

Thanks for any builders of this one who can help!

strategy

[frequencycentral]

The way I remember pinouts for these subminis is that there is a gap between pins 1 and 8, over than that they correspond to a dual opamp, so looking down on the tube is the same as looking down on a dual opamp (if, as I do, you create another gap between pins 4 and 5 for insertion into the PCB, SIL strips or whatever). Anyway, there's a little diagram showing the pinout in the schematic on the first page of this thread.