Search found 35 matches

by hgamal
22 Jun 2018, 19:47
Forum: DIY Stompbox designs
Topic: What are the challenges to designing a discrete LM3080N
Replies: 9
Views: 4064

Re: What are the challenges to designing a discrete LM3080N

I think still worth to clone one using discrete parts. Maybe a exact copy of 3080 will not produced, but a very interesting OTA will.

When I was young I dreamed with custom chip companies, delivering ICs to the people. This time has not come yet! I keep my dreams.
by hgamal
19 Jan 2017, 14:03
Forum: Pedal Debugging & Troubleshooting Support
Topic: Debugging a Line6 DL4. Help needed!
Replies: 9
Views: 523

Re: Debugging a Line6 DL4. Help needed!

The DSP56364 is the component responsible for a considerable current consumption on this circuit. If the power source is defective, non capable to drive the enough current to the circuit, the lack of DSP56364 can restore the voltage levels to the correct values. So, if the power source is defective,...
by hgamal
20 Feb 2016, 04:23
Forum: Modern Stompbox Effects (1975 - ...)
Topic: FlyRig5 [schematic]
Replies: 3
Views: 3024

Re: FlyRig5 [schematic]

Please, can you send a more detailed photo from left side of the board, the right place where FV-1 circuit is placed?
by hgamal
16 May 2015, 14:32
Forum: DIY Stompbox designs
Topic: ETI Valve Distortion Unit
Replies: 7
Views: 4070

Re: ETI Valve Distortion Unit

I've made some enhancements to the image in order to be more readable.
by hgamal
09 Apr 2014, 15:08
Forum: Ready-To-Build Effect Projects
Topic: High Voltage Solid State input stages (tube equivalent)
Replies: 21
Views: 930

Re: High Voltage Solid State input stages (tube equivalent)

I would like to see some non linear response comparison between the two circuits. I will be very surprised if the two circuits present the same signal distortion!
by hgamal
02 Feb 2014, 04:33
Forum: Amplifiers
Topic: good tube amp without pre-amp
Replies: 15
Views: 5969

Re: good tube amp without pre-amp

hi all, im just looking for a small simple tube amp schematic, without the pre-amp just amp, cause i want mi guitar signal the clearer and natural possible without any filter on it.... This document is written in a strange language (sorry I write better portuguese than english), but I think all sch...
by hgamal
08 Jan 2014, 11:13
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Digitech - PDS 1002 Delay [schematic]
Replies: 59
Views: 39800

Re: Digitech - PDS 1002 ( Delay ) [schematic]

I know its sounds like an aggravated assault, but, try this:

https://www.ebay.com/itm/MC14007UBCPG-40 ... 2c73913a5b
by hgamal
07 Jan 2014, 14:19
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Digitech - PDS 1002 Delay [schematic]
Replies: 59
Views: 39800

Re: Digitech - PDS 1002 ( Delay ) [schematic]

I took much time to make mine work again. I have tested all ICs and all of them were ok. After a long and big fight, I realized the problem were on the electrolytic capacitors. Because the pedal was turned off for much time, some electrolytic capacitors went out of specification. In order to "revive...
by hgamal
04 Dec 2012, 21:16
Forum: Software Room
Topic: POLL: What is your preferred PCB design software?
Replies: 31
Views: 32747

Re: Preferred PCB design software

other = kicad
by hgamal
24 Nov 2012, 15:07
Forum: Boutique Stompboxes dissected...
Topic: Cusack Tap A Delay Gutshots
Replies: 18
Views: 2849

Re: Cusack Tap A Delay Gutshots

mrkaploca wrote:something similar u mean ?
http://circuitworkshop.com/forum/index.php?topic=1083.0
Yes, but we must to vary the current, not the voltage on control pin!
by hgamal
23 Nov 2012, 23:06
Forum: Boutique Stompboxes dissected...
Topic: Cusack Tap A Delay Gutshots
Replies: 18
Views: 2849

Re: Cusack Tap A Delay Gutshots

~arph wrote:But where is the digipot ? I suspect a PWM controlled current sink
Maybe it use a FET (or other device) to control the delay, Although it is difficult to control the FET to get a linear resistance variation, the PIC can monitor the fck output (pin 5) in order to achieve the correct delay!
by hgamal
26 Jan 2011, 03:35
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: EH - LPB-1
Replies: 6
Views: 3733

Re: EH - LPB-1

guts from the first series: http://img1.iwascoding.de/2/2008/02/11/28CF27521F0D47F589717612B466B731.jpg http://img1.iwascoding.de/2/2008/02/11/12333D544F7841AF9F9DB74B3ADED9FA.jpg http://img1.iwascoding.de/2/2008/02/11/0CAE0B79FBB7468C853ACF8114A3DE7A.jpg http://img1.iwascoding.de/2/2008/02/11/D15A...
by hgamal
02 Jan 2011, 01:40
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Marshall - SV-1 Supervibe Chorus [schematic]
Replies: 17
Views: 11701

Re: Marshall Supervibe Chorus SV-1 schematics [schematic]

Valve Head wrote:Here are the schematics for the SV-1. This should get you started.
Thank you very much!
by hgamal
31 Dec 2010, 21:02
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Marshall - SV-1 Supervibe Chorus [schematic]
Replies: 17
Views: 11701

Marshall - SV-1 Supervibe Chorus [schematic]

I've got a Marshall Supervibe SV-1 but it is not working. Does anybody has its schematics?
by hgamal
06 Jul 2010, 02:00
Forum: Ready-To-Build Effect Projects
Topic: Freestompboxes Baja Mini Tube Overdrive [verified]
Replies: 77
Views: 7401

Re: Freestompboxes Baja Mini Tube Overdrive [verified]

Baja,

great work!

Can't you post the schematics?

Why not use an standard voltage regulator as 7806 in order source tube filaments? We can use the BOX as thermal dissipator. Actually, AC 10v power source isn't what we call a standard value!
by hgamal
28 May 2010, 22:00
Forum: Amplifiers
Topic: tube amp without power transformer.... is it possible?
Replies: 12
Views: 3840

Re: tube amp without power transformer.... is it possible?

The power transformer function on the tube amp circuit is not only to source it. It has the function of isolate the user from the power plug on the wall. Without the power transformer, the user will have always to pay attention how to plug other electronic device to the amp. The polarity inversion w...
by hgamal
17 Apr 2010, 20:36
Forum: Parts Sourcing & Trading
Topic: HLJ0544 Jack
Replies: 7
Views: 1002

Re: HLJ0544 Jack

I still can't find those JACK. My RV3 i svery scratchy. Can anybody help me?
by hgamal
13 Jan 2010, 11:47
Forum: Amplifiers
Topic: add master volume to Fender Vibrolux 5F11
Replies: 2
Views: 1746

Re: add master volume to Fender Vibrolux 5F11

Try this, but I have not tested. Beware: High voltages inside.

Image
by hgamal
19 Dec 2009, 12:33
Forum: Parts Sourcing & Trading
Topic: HLJ0544 Jack
Replies: 7
Views: 1002

HLJ0544 Jack

I have a BOSS RV3 pedal with scratch output jacks . Accordingly to the BOSS RV-3 Service Notes the jacks are HLJ-0554-01-010. I have searched on ebay, google, mouser, etc without success. As I seen, several manufacturers use this kind of jack, but I have not found any clue where to get one. I've tri...
by hgamal
31 Oct 2009, 19:38
Forum: Pimp-My-Cheap-Pedal
Topic: Convert Maxon AD80 to Boss DM-2
Replies: 0
Views: 892

Re: Convert Maxon AD80 to Boss DM-2

No you can not. 3005 and 3205 have different ways voltage source. One use positive ground and another negative ground, There is no way to change one for another without to change the circuit board.