Search found 202 matches
- 19 Jul 2020, 20:19
- Forum: Boutique Stompboxes dissected...
- Topic: Keeley - Java Boost
- Replies: 37
- Views: 10586
Re: Keeley - Java Boost
If you cannot set the right values with the potentiometers the OC44 does not have the right values for HFE (gain) and leakage current. Oddly enough, this OC44N tested fine, although with a smaller hFE than it would be ideal - about 60. I think I'll go with R. G. Keen's wisdom for now - it's simply ...
- 19 Jul 2020, 11:05
- Forum: Boutique Stompboxes dissected...
- Topic: Keeley - Java Boost
- Replies: 37
- Views: 10586
Re: Keeley - Java Boost
Ok, here's one for the column "I don't know why it works (but I like it)". I've build a Keeley Java Boost using johnk's PCB, and one of the new Mullard OC44's that Banzai sells: KJB OC44.jpg However, for the life of me I can't get the voltages under cca 9V. The ones I've decided to settle ...
- 30 Mar 2020, 18:08
- Forum: Pimp-My-Cheap-Pedal
- Topic: Dunlop - Cry Baby GCB-95: how to improve it for cheap
- Replies: 234
- Views: 190572
Re: Dunlop - Cry Baby GCB-95: how to improve it for cheap
What effect on the sound does bringing the 4.7uf down to 4uf have? It's subtle, but it's worth it if you: a) like the sound of the original Italian Jens b) play loud (preferably in front of people, and with other people's help) and can really hear (and feel) what's going on with your sound c) don't...
- 15 Jan 2019, 14:29
- Forum: Amplifiers
- Topic: Capacitors in Mesa Boogie Dual Rectifier
- Replies: 25
- Views: 7233
Re: Capacitors in Mesa Boogie Dual Rectifier
Actually, they have a higher failure rate than electrolytics, all of the data suggests. One of the possible reasons for using them is distortion. When placed on signal path, they tend to introduce non-linearities, the sonic signature of which is very much respected in both pro-audio (Rupert Neve) an...
- 28 Nov 2018, 10:43
- Forum: Modern Stompbox Effects (1975 - ...)
- Topic: Dunlop - JBF-3 Joe Bonamassa Fuzz Face [schematic]
- Replies: 161
- Views: 105192
Re: Dunlop - JBF-3 Joe Bonamassa Fuzz Face [schematic]
Rocker83 wrote:Can anyone decipher the correct values and types of resistors and the capacitors in this JBF-3?
- 03 Oct 2018, 17:15
- Forum: Ready-To-Build Effect Projects
- Topic: Fred Briggs - Super OCD
- Replies: 64
- Views: 10975
Re: Fred Briggs - Super OCD
I always use ICL7660 S CPA, as Bill Finnegan have, as should you and as should everybody. The charge pump frequency is moved to 20 kHz and above with that model (I forgot the exact value), so that the whine doesn't interfere with your guitar signal. It's safe to say that, whenever you see MAX1044 or...
- 01 Oct 2018, 08:22
- Forum: Ready-To-Build Effect Projects
- Topic: Fred Briggs - Super OCD
- Replies: 64
- Views: 10975
Re: Fred Briggs - Super OCD
Here are the working voltages (I've used deeno's PCB).
- 05 Jul 2018, 05:06
- Forum: Pedal Debugging & Troubleshooting Support
- Topic: Rat Sounds Wrong
- Replies: 16
- Views: 878
Re: Rat Sounds Wrong
I think that's ok. By all means check the other values too.
- 04 Jul 2018, 14:38
- Forum: Pedal Debugging & Troubleshooting Support
- Topic: Rat Sounds Wrong
- Replies: 16
- Views: 878
Re: Rat Sounds Wrong
You've got two resistors in the lower right corner that look like metal oxide ones, ie. they could be a part of the mod. I forgot which values are standard there, but check it out.
- 31 May 2018, 14:09
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: WEM, Watkins, Rush - Pepbox, Rush Pep Box [schematic]
- Replies: 121
- Views: 66282
Re: WEM, Watkins, Rush - Pepbox, Rush Pep Box [schematic]
I've tried to build the PNP Germanium version using a PCB from here: http://effectslayouts.blogspot.com/2015/09/wem-pep-box.html However, even with multiple transistor changes (70-90 hFE works best), the unit sounds nice (for a raspy, bass-heavy fuzz), but pops obnoxiously when (dis)engaged and lose...
- 08 May 2018, 05:58
- Forum: Modern Stompbox Effects (1975 - ...)
- Topic: POWER SUPPLY ISOLATED
- Replies: 17
- Views: 4891
Re: POWER SUPPLY ISOLATED
thanks, now nobody made a similar power supply, I can not see any schematic here? Power supply with multiple isolated outputs = transformer with multiple 12V outs + a number of PCB's holding the capacitors and regulators, all in one housing. Use this board and have it made into a number of PCB's: h...
- 04 Jan 2018, 12:11
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: Sola Sound - Tonebender Mark II Professional [schematic]
- Replies: 692
- Views: 271057
Re: Sola Sound - Tonebender Mark II Professional [schematic]
I've ordered a ToneBender set from diyguitarpedals.com.au - http://www.diyguitarpedals.com.au/shop/index.php?main_page=product_info&cPath=3&products_id=6 The transistors look the part: AC125 01.jpg AC125 02.jpg It came with these marked values: Q1 Collector current (IC) 828, Leakage (ICL) 15...
- 12 Dec 2017, 18:04
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: Sola Sound - Tonebender Mark II Professional [schematic]
- Replies: 692
- Views: 271057
Re: Sola Sound - Tonebender Mark II Professional [schematic]
I've seen that SmallBear now stocks Amperex 2N281 transistors which are made in Holland, and according to this excellent read (https://sites.google.com/site/transistorhistory/Home/european-semiconductor-manufacturers/philips) they should correspond to Phillips OC72 type. I've ordered a set and recei...
- 11 Dec 2017, 22:08
- Forum: Ready-To-Build Effect Projects
- Topic: Baja B K Butler Tube Driver [verified]
- Replies: 301
- Views: 76798
Re: Baja B K Butler Tube Driver [verified]
OK, third time's the charm. Here are all of the interconnects... Dont Forget The Interconnects.jpg ...or, in the words and pictures of another builder... LayerLinks01.jpg Also, please be advised - all of the diodes (1N4007, 1N4148, 2V5 zener) are oriented wrong on Bajaman's layout . Capacitors and L...
- 03 Dec 2017, 12:58
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: Sola Sound - Tonebender Mark II Professional [schematic]
- Replies: 692
- Views: 271057
Re: Sola Sound - Tonebender Mark II Professional [schematic]
I'll try. One question, if I may...
I've got a small stash of germanium transistors that I can experiment with. Given the above numbers, what kind of leakage (IC and/or ICE0) am I looking for?Electric Warrior wrote:It's too little leakage for your bias setup...
- 03 Dec 2017, 07:45
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: Sola Sound - Tonebender Mark II Professional [schematic]
- Replies: 692
- Views: 271057
Re: Sola Sound - Tonebender Mark II Professional [schematic]
Thanks! Any recommendations? Which voltage do I aim for?Electric Warrior wrote:Considering your supply voltage, Q1C is rather high. I'd definitely use a bigger resistor on its base.
- 02 Dec 2017, 22:24
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: Sola Sound - Tonebender Mark II Professional [schematic]
- Replies: 692
- Views: 271057
Re: Sola Sound - Tonebender Mark II Professional [schematic]
It's too little leakage for your bias setup... Well, that's exactly the greatest part of the problem - those are the transistors that are supposed be selected to work well in a ToneBender by the good people in BYOC, right? If so, why aren't they? They were biased to around 0.16V on Q2C. Great info,...
- 02 Dec 2017, 15:13
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: Sola Sound - Tonebender Mark II Professional [schematic]
- Replies: 692
- Views: 271057
Re: Sola Sound - Tonebender Mark II Professional [schematic]
How are the other transistors biased? For the sake of posterity, here's the proverbial shakedown. First, if you look into the BYOC ESV 2-Knob ToneBender schematic... BYOC ESV 2-Knob ToneBender Schematic.jpg + ...you'll see that R2 should be lowered to 10K, which I did (except I didn't have a 10K ca...
- 30 Nov 2017, 13:02
- Forum: Vintage Stompbox Corner ( ... - 1975)
- Topic: Sola Sound - Tonebender Mark II Professional [schematic]
- Replies: 692
- Views: 271057
Re: Sola Sound - Tonebender Mark II Professional [schematic]
Btw, I've built a ToneBender MkII and wanted to repeat the experience, but with as much mojo parts as humanly possible. That led me to BYOC ESV 2-knob Bender kit, and so I've purchased one a couple of weeks ago. Although the BYOC website mentions "a set of N.O.S. Philips OC76 germanium transist...
- 24 Nov 2017, 13:37
- Forum: Ready-To-Build Effect Projects
- Topic: Baja B K Butler Tube Driver [verified]
- Replies: 301
- Views: 76798
Re: Baja B K Butler Tube Driver [verified]
Forgot two...