Schaller Tremolo / Hearthrob Tremolo

rocklander · Post by **rocklander** » 05 Jan 2011, 19:05

thanks Seiche.. yeah sorted it at the time, but can't remember how.. heh..

SamuraiFX · Post by **SamuraiFX** » 20 Jan 2011, 18:31

Hi everybody, this is my last built, shaller tremolo with topopiccione schematics:

Uploaded with ImageShack.us

poodlebra · Post by **poodlebra** » 12 Feb 2011, 15:27

IvIark wrote:Here's one I did a while ago based on the same Vero, just to make it larger.

cheers for redrawing, but there are a couple of errors on it which had me scratching my head for a while.

- You have R15 marked as R5 (spdt1 > gnd)
- the real R5 is connected to the wrong track. should be track C, not B as you have it.

now, if only i could get this to work. no throbbing at all

IvIark · Post by **IvIark** » 12 Feb 2011, 15:43

That was just based on the previous version by nokaster which I only had a small version of and was difficult to read. I did do a smaller layout myself from the schematic though, I'll dig it out and post it.

k1rkyd · Post by **k1rkyd** » 15 Feb 2011, 15:39

So now that we have a WET and DRY mix (DWELL) what would the chances be of adding a depth control ??
I added a variable voltage trim pot to the base of Q1 and it didn't work very well at all.. (as i expected) !
I had a look at the schematic, and i dont think i'm experienced enough to know where to put the depth but it would be great to have??

If anyone has any ideas, please dont hesitate to reply

Thanks again guys,
K1RKYD

Jimmy-H · Post by **Jimmy-H** » 16 Feb 2011, 10:14

Hi there,

It's been a while, but I finally had the time to update my Heartube from the last page.
I removed Q2 because it had no purpose.
Now the build is how it supposed to be.
Infact you can use any (clean-) booster with this lfo.
So here are the updated files (the transfers must be decreased by 50% if you use them):

7dust · Post by **7dust** » 19 Mar 2011, 20:06

Need, help.

These is my first post on freestompboxes. I just finish building the Hearthrob Tremolo, but something went wrong, i have led on, i have sound when i engaged and i have sound when the pedal is non-engaged, but i don't have effects when i engaged the 3PDT. I also notice that the pot25KB works "similiar to kind of volume". I use GGG offboard wiring, for 3PDT, and i also use 2n5088.

All components are correct values (cap, res, transistors), i used the MarkM Layout.

I also have the capacitor in positive and negative order correct.

Thanks.

http://www.generalguitargadgets.com/dia ... a841b3e85a

rocklander · Post by **rocklander** » 19 Mar 2011, 21:24

are your transistors orientated correctly?
have you taken the 3pdt out of the equation and tried the effect directly?

close up pictures of both the component and solder side would help peeps her to help

RnFR · Post by **RnFR** » 19 Mar 2011, 21:47

it was ages ago, but I never got that markm layout working either. is it verified? I've always wanted to give this circuit another try.

rocklander · Post by **rocklander** » 19 Mar 2011, 21:50

RnFR wrote:it was ages ago, but I never got that markm layout working either. is it verified? I've always wanted to give this circuit another try.

I've made about 5 of these on the MarkM layout... all worked fine for me... is there any chance there's more than one MarkM layout out there?

this is the one I used.
http://www.aronnelson.com/gallery/main. ... T.gif.html

7dust · Post by **7dust** » 19 Mar 2011, 22:39

Thanks rocklander for fast reply..

I just figure the problem, it was one of tracks on PCB that was broken, small to find it...

The multimeter did help a lot,it's ok... for now

Thanks

da5hcharl · Post by **da5hcharl** » 05 Apr 2011, 00:56

Just finished debugging mine, or at least getting it to work. Poodlebra helped immensely by pointing out r15 was linked to the wrong track on one vero drwng. Third successful build! Gradually working up to something really tough

da5hcharl · Post by **da5hcharl** » 05 Apr 2011, 13:04

I know I'm the last poster on this topic, but I wanted to mention a few things about my build. I couldn't source 2n5088's at my local parts shop (EPO) which is usually excellent, so i used the NTE "equivalent" NTE123AP's. I was also wondering if it was par for course for the speed switch to have a sweet spot? It seems like mine only works to up the speed in a limited range before washing out the trem effect. It's also worth noting that i went with all tantalum caps, just because i could find all of my values and didn't want to use electrolytics.

Barcode · Post by **Barcode** » 05 Apr 2011, 20:42

da5hcharl wrote:I know I'm the last poster on this topic, but I wanted to mention a few things about my build. I couldn't source 2n5088's at my local parts shop (EPO) which is usually excellent, so i used the NTE "equivalent" NTE123AP's. I was also wondering if it was par for course for the speed switch to have a sweet spot? It seems like mine only works to up the speed in a limited range before washing out the trem effect. It's also worth noting that i went with all tantalum caps, just because i could find all of my values and didn't want to use electrolytics.

what size speed pot are you using?

da5hcharl · Post by **da5hcharl** » 06 Apr 2011, 05:26

1meg linear taper speed pot. that works great, from slow to relatively fast. then on the "speed switch" i have it toggling between going direct to ground and going through a 220 ohm resistor and then to ground. It does up the speed in the 3/4-7/8 range of the speed pot, but any where other then that i get a couple of cycles and then it just pretty much fades into no effect. I really like the effect as is, but if i could have a full range of faster trem i'd dig it even more. I really appreciate the reply and interest in helping. This board is awesome.

Barcode · Post by **Barcode** » 06 Apr 2011, 15:45

Well, there are two possible issues I can see.

One is that eventually, a fast tremolo does become a solid sound. Tremolo mutes a signal at a specific interval. Verify the resistor tacked to the rate pot and ensure it is 27K.

The other issue has to do with the LFO. 1M is a HUGE rate pot, and will give you a wide sweep of speed. But with tolerances of pots being what they are, it teeters on the edge of causing the LFO not function. The LFO (low frequenct oscillator) is what cycles/causes the tremolo. The resistance of the speed pot and it's series resistor are a crucial part of the LFO. Once the resistance gets to a certain point, the LFO will no longer oscillate.

Also, bear in mind that the way the speed switch works is to short a resistor across the rate pot to reduce it's value. So it's really only going to double the rate at higher points on the knob, because of the way parallel resistors work. At lower settings on the knob, there won't be much difference in rate between the switched positions.

da5hcharl · Post by **da5hcharl** » 07 Apr 2011, 00:26

It sounds like it's working to spec. I really appreciate the explanation of how the circuit works, I don't have much of a background in electronics theory. I will verify the actual value of the resistor that you mentioned. All in all it is a really great little tremolo. Thanks muchly for taking the time to explain the what why and how to me!

SirElwood · Post by **SirElwood** » 08 Jul 2011, 17:05

Hi!

I just got schaller tremolo pedal. It looks like it's been modified over the years, and it does not match that factory schematic. It looks like someone has added a dc-jack and replaced Q1 (badly) whit some small transistor with no markings on it at all. To me it also looks like some electrolytic caps has been changed. Being nitpick as I am, I would like to change atleast that transistor properly whit original part. Can anyone tell me when this pedal was made? All other transistors are BC549. And amplitude pot wiring looks weird to me...

Anyway... Here are some pictures. Ask for more if needed.

It's not the neatest thing in the world... Might be a nice project to make it neat and clean, because it sounds very good.

rocklander · Post by **rocklander** » 07 Oct 2011, 19:16

woot! I can finally post a verified layout

built this in the last week and it worked first time.
1590a heartthrob.
schem is the one posted earlier in the thread

layout

: Hearthrob1590a-pcb1.0(c).jpg (76.5 KiB) Viewed 3555 times

pcb

: Hearthrob1590a-layout1.0(c).jpg (77.27 KiB) Viewed 3555 times

pdf (paper size A4)including layout, schem and correct sized pcb, and also the expresspcb files in the zip

hearthrob.zip: (227.75 KiB) Downloaded 261 times

boblob · Post by **boblob** » 14 Oct 2011, 17:30

I have a 90s era one too (which sounds really superb), but rather than modding it with a DC jack and LED I opted to clone it instead. There are a couple of differences from the old factory schematic - most notably there is a 2.2uF going from the base of the modulating transistor to ground. This cap *greatly* reduces feedtrough (LFO ticking) and I recommend adding it. Transistors are BC549B, but I hear no disernable difference between them and BC109s or 2N5088s.

True bypass switch pop is also a real bastard on this one. I went with much smaller film input and output coupling caps and a 47K pulldown at the end instead of the 1M that the Heartthrob has; this somewhat improves matters. You could always *gulp* not go true bypass and stick with the factory switching - my original isn't tb and it sounds just fine as is.