Search found 216 matches

by gigelmargel
30 May 2020, 07:35
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

Your work is fantastic, Manfred! My CS-1 is exactly as in your picture, but on my both P873A is written 1A, while in your picture is written 1F and 1G, which may suggest that are different types, as for the transistors? When I bought my CS-1, it was damaged due to a drained battery right in the rect...
by gigelmargel
29 May 2020, 21:24
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

Today, I had some free time and I put back the HTVs. It sounds better than the Chinese VTLs, but still is not so strong as in the videoclips. Now, it has enough volume with the output resistor lowered from 150K to 10K, even with the same resistor and the Chinese VTLs it had a huge volume drop. So, I...
by gigelmargel
29 May 2020, 07:18
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

I measured both HTVs for 3 to 5 times, because I was very intrigued and I know that a optocoupler needs some time to accommodate with the light. So, i think that the measured values are OK. But, taking into account that it's a 40 years old stompbox, it's hard to tell if the HTVs was selected or are ...
by gigelmargel
28 May 2020, 18:03
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

Hello, Manfred! I measured the optocouplers using fixed resistors as you said and the results are in this Excel file: LDRs.xlsx . After I have finished measuring the Chinese VTLs, I thought I'd try to measure the original HTVs optocouplers and I have many surprises: During this operation, I have a l...
by gigelmargel
28 May 2020, 07:07
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

"Could you measure the resistance of your LDR optocoupler in function of the LED current?"
I have no ideea how to do that, Manfred :(
I know how to vary a voltage (using a pot in series with a battery), but I have no idea how to vary the current.
If you explain me, of course that I will do :)
by gigelmargel
27 May 2020, 06:33
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

Very interesting, Manfred!
The plot shows that the modded detector ensures a stronger compression?
by gigelmargel
26 May 2020, 06:59
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

Very interesting, Manfred! It's clear that I was totally wrong about PH2. I will try to understand much better what you said/plot :)
by gigelmargel
25 May 2020, 06:51
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

Hello, Manfred! I have no chance to use the original circuit, because one optocoupler (PH2) is completely dead (an infinite resistance of LDR all the time) and PH1 is almost dead (an intermittent infinite resistance of LDR). Both have the LED voltages around 1.7-1.8 volts. Anyway, can you tell me wh...
by gigelmargel
24 May 2020, 19:15
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

I think that the Chinese VTLs that I bought are really a big shit. I've finished an EQD Warden clone using another Chinese VTL and it sounds like crap, mainly it has a too big attack. I will in the next day to replace the VTL with a LDR+LED and to see what it will happen. I suspect that's the proble...
by gigelmargel
18 May 2020, 07:15
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Re: Questions about Boss CS-1

I am very patient, no problem :)
by gigelmargel
13 May 2020, 23:20
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Questions about Boss CS-1
Replies: 20
Views: 2183

Questions about Boss CS-1

Hello all! Before starting my story, here is the schematic of Boss CS-1 (there were 2 variants - mine is V2, with the red values): Boss CS-1 variants.jpg I've bought a Boss CS-1 from '80s at a very good price, but it didn't work: almost no compression and a big boost of signal. This looks very stran...
by gigelmargel
20 Mar 2020, 16:23
Forum: Pedal Debugging & Troubleshooting Support
Topic: It can be used a light bulb + LDR in DOD 280 compressor?
Replies: 7
Views: 406

Re: It can be used a light bulb + LDR in DOD 280 compressor?

Check a Univibe schem and add a driver transistor to handle much current... Don't think it can handle high frequencies because the filament glow has some kind of inertia (escpecially if the rise/fall time of LDRs is long)... Thank you, lolbou! I thought about that, but I don't have enough knowledge...
by gigelmargel
20 Mar 2020, 16:21
Forum: Pedal Debugging & Troubleshooting Support
Topic: It can be used a light bulb + LDR in DOD 280 compressor?
Replies: 7
Views: 406

Re: It can be used a light bulb + LDR in DOD 280 compressor?

Maybe I need to use a higher voltage? You should experiment with decreasing current limiting resistor value. Refer to Ohm's law. Good idea...thx! I've put a 10K linear pot in place of the limiting resistor value, but light bulb don't want to light at all :cry: Maybe it simply has no time to light u...
by gigelmargel
19 Mar 2020, 11:13
Forum: Pedal Debugging & Troubleshooting Support
Topic: It can be used a light bulb + LDR in DOD 280 compressor?
Replies: 7
Views: 406

Re: It can be used a light bulb + LDR in DOD 280 compressor?

gigelmargel wrote:
plush wrote:
gigelmargel wrote: Maybe I need to use a higher voltage?
You should experiment with decreasing current limiting resistor value.

Refer to Ohm's law.
Good idea...thx!
I've put a 10K linear pot in place of the limiting resistor value, but light bulb don't want to light at all :cry:
by gigelmargel
18 Mar 2020, 19:25
Forum: Pedal Debugging & Troubleshooting Support
Topic: It can be used a light bulb + LDR in DOD 280 compressor?
Replies: 7
Views: 406

Re: It can be used a light bulb + LDR in DOD 280 compressor?

plush wrote:
gigelmargel wrote: Maybe I need to use a higher voltage?
You should experiment with decreasing current limiting resistor value.

Refer to Ohm's law.
Good ideea...thx!
by gigelmargel
17 Mar 2020, 07:52
Forum: Pedal Debugging & Troubleshooting Support
Topic: It can be used a light bulb + LDR in DOD 280 compressor?
Replies: 7
Views: 406

It can be used a light bulb + LDR in DOD 280 compressor?

Hello all! I've finished a DOD 280 compressor clone using this layout: http://tagboardeffects.blogspot.com/2012/12/dod-280-compressor.html . I tried a couple of VTLs and LED+LDR combinations and I like almost all due to their different flavors :D After that, I tried to use a 1.5V/50mA light bulb wit...
by gigelmargel
10 Aug 2019, 09:10
Forum: DIY Stompbox designs
Topic: How to calculate the resonant frequency of a GCB-95?
Replies: 4
Views: 1503

Re: How to calculate the resonant frequency of a GCB-95?

I have a Zakk Wylde Wah which I want to modify in a Dimebag Wah. The main problem is that ZW Wah has a 500 mH inductor, while in DD Wah the inductor is 535 mH, so I must to recalculate all the 6 values of C7. Hi Radu, I didin't know exactly the differences between these two models. Can you post the...
by gigelmargel
09 Aug 2019, 08:01
Forum: DIY Stompbox designs
Topic: How to calculate the resonant frequency of a GCB-95?
Replies: 4
Views: 1503

Re: How to calculate the resonant frequency of a GCB-95?

Hi gigelmargel, The resonant circuit is comprised by the inductor and the 10nF condenser, named C7 in the previous schematic. BUT the value of this condenser is constantly varied due a buffer action from transistor Q3 according to the potentiometer (hence: pedal) position. Take a read at this link ...
by gigelmargel
08 Aug 2019, 15:29
Forum: DIY Stompbox designs
Topic: How to calculate the resonant frequency of a GCB-95?
Replies: 4
Views: 1503

How to calculate the resonant frequency of a GCB-95?

Hello! I want to begin to modify a Dunlop GCB-95 wah, but I don't know how to calculate the resonant frequency. To be more clear, I read in the GCB-95 manual the following informations: Filter Parameter Low Pass 350 Hz ~ 450 Hz High Pass 1.5 kHz ~ 2.5 kHz Looking at the schematic below I have no ide...
by gigelmargel
29 Apr 2017, 20:09
Forum: Boutique Stompboxes dissected...
Topic: Lovepedal HiVolt
Replies: 14
Views: 6152

Re: Lovepedal HiVolt

hozy31 wrote:Hi gigelmargel, what was the link you added to lug 3 of mids pot, i can't seem to find any mention of it?
I added link in the layout from here: http://effectslayouts.blogspot.ro/2017/ ... -volt.html...in the comments you can read exactly where :)

Good luck!