Search found 27 matches

by acidfuzz
22 Aug 2019, 03:49
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Yes, it was a 2N4061 silicon. This was about ~3 years ago. Glad you found the correct cap values :) . I remember the owner did send me a pic (guts), but don't remember if the 0.1uf caps were visible.
by acidfuzz
16 Aug 2019, 05:21
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Electric Warrior: "Isn't the "D8" on the fuzz pot a date code? I've seen several with this code, but many germanium ones have it as well. The hybrid version being the last of the Zonk Is makes sense and sounds perfectly logical, but it's only an assumption. I don't think we can say for sure." Yes si...
by acidfuzz
28 Jun 2019, 20:55
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Nice! Cool to see clones coming to life. If it helps, the 2N4061 hFE was 110, obviously with zero leakage (Si). You could easily use a Ge tranny in there, but the Si does make it more temperature stable. Here's the corrected schematic with the 2.2M output resistor: https://live.staticflickr.com/6553...
by acidfuzz
25 Jun 2019, 14:00
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Manfred, No. The internal trimmer was adjusted to ~152K. Voltages were then measured with the external "FUZZ" control set at 1/2 (12 Noon) and at full clockwise rotation at room temperature (~70°F). Like in the Maestro Fuzz Tone and the MKI Tone Bender, the "FUZZ" control is essentially an external ...
by acidfuzz
23 Jun 2019, 16:57
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Here are the voltages at ~70°F with a 9V battery: 1/2 "FUZZ" Full "FUZZ" Q1: C -8.98V -8.95V B -.707V -.715V E -.656V -.676V Q2: B -.643V -.672V C -7.16V -3.632V E -0.1mV -0.1mV Q3: C -7.99V -7.51V B -51.7mV -51mV E -0.1mV -0.1mV
by acidfuzz
23 Jun 2019, 16:46
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

https://live.staticflickr.com/65535/48114733431_2e273b1972_h.jpg HybridZonkTop by Jonathan Curl , on Flickr https://live.staticflickr.com/65535/48114778268_dbdd810d8f_b.jpg HybridZonkAngle1 by Jonathan Curl , on Flickr https://live.staticflickr.com/65535/48114833042_aab62405a2_b.jpg HybridZonkAngle...
by acidfuzz
23 Jun 2019, 01:12
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Thanks Cub! I tried that, but maybe I was just confused because the video wouldn't load when previewed?

[youtube]https://youtu.be/q9I5HRkP13Q[/youtube]
by acidfuzz
22 Jun 2019, 14:58
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Yes, I did note the voltages at 1/2 "SWELL" and at full "SWELL". I did a video overview of the repair. I'd gladly post it here but freestompboxes doesn't seem to like youtube links, even with the youtube tag button. Anyone else have this problem?
by acidfuzz
22 Jun 2019, 02:43
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Please note, that's actually the wrong file. That's the trace I did before I repaired it. The 47 ohm output resistor is WRONG. It's what was in this when I got it, and there's no way in hell that it is stock. The out put level was insane with only 47ohms to tame it back. I replaced it with a 2.2 Meg...
by acidfuzz
22 Jun 2019, 02:36
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Here's the schematic for this one. Really no different than the all germanium Zonk, aside from the trimmer: https://live.staticflickr.com/65535/48106094286_2075f206d5_b.jpg Zonk Hybrid Schematic Web by Jonathan Curl , on Flickr I'll post some photos shortly. I also did an overview of the repair and ...
by acidfuzz
19 Jun 2019, 16:06
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

I don't have the pedal on my desk right now, but I'll check it against the photo night raven posted. No, not Scotty "Pro" Analog. Incidentally, I was actually accused of BEING Scotty/Proanalog when I first started doing the Acid Fuzz thing around 2009 or so. I was selling on Ebay a lot then and peop...
by acidfuzz
18 Jun 2019, 18:12
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

There's a fun article on the Zonk here: https://www.vintageguitar.com/23068/hornby-skewes-zonk-machines/ "Skewes translated that cultural shift into a business; with his wife, Madge, he founded his own musical-instrument company in ’65, from his home in Garforth, in West Yorkshire – far from swingin...
by acidfuzz
18 Jun 2019, 13:31
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Night raven is exactly correct with the 2N4061. I've personally only seen two of these beasts, but there are some photos floating around the internet. I have been unable to confirm if they are of the same pedal(s). I haven't pulled the pots and looked at date codes yet. I have to do repairs in the o...
by acidfuzz
17 Jun 2019, 19:31
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zonk Machine - middle transistor is silicon ??? trim pot
Replies: 33
Views: 10942

Re: Zonk Machine - middle transistor is silicon ??? trim pot

Yes. I actually have an identical one in the shop for repair right now. It arrived over the winter, but I haven't had the time to take a look at it yet as I have wait lists for all of our regular builds, which is how I pay the bills and feed my family. It's only the second Zonk like this I've ever s...
by acidfuzz
24 May 2014, 03:03
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Hornby Skewes - Zonk Machine / Zonk II ( JHS )
Replies: 29
Views: 18246

Re: Hornby Skewes - Zonk Machine / Zonk II ( JHS )

Hi Andre, My opinion on which Hfe/gain and current leakage for transistors going in to Zonks is that, like most vintage germanium fuzzers, there is probably quite a large amount of variation between the original pedals. Long answer short, it's subjective. One area I would watch out for is the freque...
by acidfuzz
04 Jun 2012, 13:33
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: JMI Vox - Grey Wah c. 1967
Replies: 99
Views: 47583

Re: JMI Vox - Grey Wah c. 1967

If anyone is curious about the palm wah circuit Vox built in to their Starstrem, Ultrasonic and other guitars, it is the same as the early grey Vox wah aside from a 33k resistor in parallel with the inductor. It also uses BC109B for both Q1 and Q2 rather than 2N3707. Other than that it's exactly the...
by acidfuzz
23 May 2012, 08:56
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Vox - Repeat Percussion (V 809) [schematic]
Replies: 145
Views: 89610

Re: Vox - Repeat Percussion (V 809) [schematic]

Bootle, Sorry, just saw this. For a vero layout without using an expression pedal jack on the rate, I would group the grounds from the 68nf/82K/220uf array, to the sleeve of the OUTPUT jack, as well as the ground for the 330K on lug 1 of the depth control. Group the others to the input sleeve. For a...
by acidfuzz
08 Mar 2012, 01:01
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Vox - Repeat Percussion (V 809) [schematic]
Replies: 145
Views: 89610

Re: Vox - Repeat Percussion (V 809) [schematic]

http://www.freeimagehosting.net/t/38f1l.jpg This is the version I've been building in to the Sonic Boom 3 in One pedals. It has more than enough tweakability for anything I've ever needed out of this effect. You can dial back the depth and cut pots and get a basic amp like tremolo. Dial the depth b...