Schaller Tremolo / Hearthrob Tremolo

rocklander · Post by **rocklander** » 22 Nov 2008, 09:36

I quickly put together the schem for this (the heartthrob incl markM's values [6k8 resistor at R9 instead of the 5K8 listed])if anyone is interested.
it's as yet unverified, so if anyone is interested in checking it for me I'd be grateful.
cheers
https://i167.photobucket.com/albums/u16 ... -schem.jpg

Barcode · Post by **Barcode** » 25 Nov 2008, 05:38

vanessa wrote:
John Lyons wrote:I built the pulsar a couple years ago. I made a few mods from posts in the build reports at tonepad and I liked it a lot. I sold it to a friend so I can't compare it to the heartthrob right now.

Thanks for the Fixed Trace Vanessa. There was a thread about this at DIYSBF a while back as well.

John
No problem John, That's from the thread I posted over at DIYSBF a while back. I'm not sure why they [Tonepad] never updated the pcb layout but if you build one from the modified pcb layout I posted you'll be very impressed.

I'm confused. Also on the tonepad schem, none of the lugs are connected directly to each other on R15 as far as I can tell. But both your corrected pcb and tonepad's show lugs 1 and 2 connected. thoughts?

also, from what i can tell, your corrected pcb doesn't actually change any connections, unless i'm completely dense (always a possibility

)

potatoolay · Post by **potatoolay** » 02 Feb 2009, 16:33

Built this yesterday and it works great... except for the horrible switch pop. Its built to the Heartthrob layout. 3pdt swith, no led. Has anyone else had this result? Ive tried throwing a 1.5m resistor between the neg leads and ground of both the input and output caps, but it didnt change anything. Im not sure that I worded that right... 1.5m res from input cap (-) to ground and 1.5 res from output cap (-) to ground.

Barcode · Post by **Barcode** » 02 Feb 2009, 18:25

potatoolay wrote:Built this yesterday and it works great... except for the horrible switch pop. Its built to the Heartthrob layout. 3pdt swith, no led. Has anyone else had this result? Ive tried throwing a 1.5m resistor between the neg leads and ground of both the input and output caps, but it didnt change anything. Im not sure that I worded that right... 1.5m res from input cap (-) to ground and 1.5 res from output cap (-) to ground.

is it in line with other pedals? if so, and they are true bypass designs, place pop resistors on them as well. if not or if that doesn't work, replace your input and output caps on this pedal, then if no change on all your others. The pop is generally due to leaky caps, which electros are notrious for. the reason a resistor to ground solves the problem in most cases is that it gives the leaking voltage a path to ground to bleed off. without them, when you connect the guitar and/or output to the circuit by flipping the switch there is stored current from that leaky cap that discharges to your guitar and/or the output jack and causes the pop.

potatoolay · Post by **potatoolay** » 02 Feb 2009, 20:21

Thanks for the reply. It pops by itself as well as in the chain with other effects. I havent tried it with my tuner that is buffered, but Im pretty confident that it wont make a difference.

That is what I could figure that the problem/solution is as well at this point. The caps are new, but I guess I could have damaged them when soldering..?

Barcode · Post by **Barcode** » 02 Feb 2009, 21:57

potatoolay wrote:Thanks for the reply. It pops by itself as well as in the chain with other effects. I havent tried it with my tuner that is buffered, but Im pretty confident that it wont make a difference.

That is what I could figure that the problem/solution is as well at this point. The caps are new, but I guess I could have damaged them when soldering..?

occasionally you can also just get a bad part or two. i've gotten a few bad caps before, they work fine, but they leak excessively and cause that pop. usually that has fixed it. I also try whenever possible (when values and size allow) to avoid using electros, as my own personal experience is that they leak most often. not sure of anyone else's experience though.

potatoolay · Post by **potatoolay** » 03 Feb 2009, 00:16

thanks. Im swapping the caps right now. hopefully that will take care of it. I usually try to use poly film caps but since this is the first tremolo Ive built, I just used what was on the layout. I appreciate the help.

potatoolay · Post by **potatoolay** » 03 Feb 2009, 15:18

changing the caps didnt do anything. HOWEVER... changing the input resistor to a 180K took away the pop. I did notice a little bit of dirt with a lot of attack when the original resistor (47K) was still in place, but the 180K seems to have pulled the majority of that out as well.

Barcode · Post by **Barcode** » 04 Feb 2009, 01:29

glad you got it worked out!

FAC · Post by **FAC** » 17 Feb 2009, 22:32

Hi guys, I just put this together on vero and it's acting a bit...weird...

I just hooked everything up without a bypass for now, but I am not getting any effect, just the clean tone. If I however disconnect the negative battery lead and just tap it onto the input ground, I get a beautiful tremolo effect, which fades out... any ideas?

FAC · Post by **FAC** » 21 Feb 2009, 00:19

I did Mark's PCB just now and it's the same, mind you I'm not tapping the neg on the ground anymore, it's hooked up. The depth pot seems to be acting like a volume control, and I can hear a tremolo effect for a few moments if I turn the speed pot, but again it just fades out into regular unaffected tone...

I'm using bc550's instead of the 5088's, which should be fine, other than that I'm going by Mark's part list...

Have quadruple-checked all connections, cap and transistor orientation, res values...

I also sheered some hair off my head with my soldering iron, all in all a pretty crappy Friday night

Barcode · Post by **Barcode** » 21 Feb 2009, 02:56

did you salvage any parts from your other build? sounds like a burnt out transistor...

FAC · Post by **FAC** » 21 Feb 2009, 03:38

Barcode wrote:did you salvage any parts from your other build? sounds like a burnt out transistor...

Only salvaged the resistors, wanted to make sure the caps and transistors were ok. I also put the transistors in sockets on this one so I could change them out...

...I just realized, I didn't reverse the 550's... it works now, and for the dwell control, I must have been looking at the schaller schematic since I bought a 50k pot, must be why it's acting a bit funky

This was my first ever build, happy to have it working, hopefully I won't have to ask stupid questions again

rocklander · Post by **rocklander** » 21 Feb 2009, 09:48

congratulations

it's a great feeling isn't it

FAC · Post by **FAC** » 21 Feb 2009, 12:43

rocklander wrote:congratulations

it's a great feeling isn't it

Sure is, can't wait to box this and use it live!

Have to wait patiently now for my enclosures from the US, a Hammond 1590B style box costs around $30 here in Iceland

FAC · Post by **FAC** » 04 Mar 2009, 17:22

greenskull wrote:I really like this one a lot, but I'm having a problem with distortion at slower speeds and when I strike chords. Just my build, or has anyone else experienced this? I used 2n5089's instead of 2N5088's.
Viva Markm!!!!!!!!!!!!

Did anyone else have this problem? Or better yet, a fix?

RnFR · Post by **RnFR** » 04 Mar 2009, 20:12

FAC wrote:
greenskull wrote:I really like this one a lot, but I'm having a problem with distortion at slower speeds and when I strike chords. Just my build, or has anyone else experienced this? I used 2n5089's instead of 2N5088's.
Viva Markm!!!!!!!!!!!!
Did anyone else have this problem? Or better yet, a fix?

the 5089's are a very high gain transistor. I can't speak from experience with this circuit, but that could be your reason for the distortion. you might want to try something with lower gain.

FAC · Post by **FAC** » 04 Mar 2009, 20:29

RnFR wrote:
FAC wrote:
greenskull wrote:I really like this one a lot, but I'm having a problem with distortion at slower speeds and when I strike chords. Just my build, or has anyone else experienced this? I used 2n5089's instead of 2N5088's.
Viva Markm!!!!!!!!!!!!
Did anyone else have this problem? Or better yet, a fix?
the 5089's are a very high gain transistor. I can't speak from experience with this circuit, but that could be your reason for the distortion. you might want to try something with lower gain.

Tried both 5088's and 550's, all the same

RiGLEY · Post by **RiGLEY** » 20 Mar 2009, 13:29

Can somebody please recommend me a mod. for an expression pedal input for the speed control?
Thanks!

~arph · Post by **~arph** » 20 Mar 2009, 13:33

RiGLEY wrote:Can somebody please recommend me a mod. for an expression pedal input for the speed control?
Thanks!

You'll have to put that in place of the speed pot, with a swithcing jack. I do not know what the typical expression pedal resistance is, but if it is less then 1 meg you need a different approach. (LED/LDR)