Interfax - Harmonic Percolator [schematic]
- theblackman
- Resistor Ronker
looking forward to hearing the results of this
- theblackman
- Resistor Ronker
https://cgi.ebay.com.au/Boutique-qualit ... 7C294%3A50
i wonder what diodes this guy is using his one sounds pretty good from the demo.
i wonder what diodes this guy is using his one sounds pretty good from the demo.
I think Timhulio is a member here. I know he is a member of the OSG forum where i sometimes post.
His percolators sound like mine with 1n34s or 1n60. NOt quite the same as the collins clone a little more treble on the clipping side. Nice effects, his new telstar pedal looks fun.
His percolators sound like mine with 1n34s or 1n60. NOt quite the same as the collins clone a little more treble on the clipping side. Nice effects, his new telstar pedal looks fun.
- DougH
- Transistor Tuner
I picked them up from a local surplus electronics place. They only had a few and I got 4 of them. If you google for them I've seen places selling them. I'm going to measure the fwd voltage on them first.JJ Gabor wrote:Thanks Doug.
where did you get your 1n695s from??
couldn't find them anywhere...
I did read that thread a while back and gleamed quite a lot of useful info from it. Loads of ideas for the breadboard.
"You have just tubescreamered or fuzzfaced yourself " -polarbearfx
I have a question about the voltage readings.
Q1 both the base and collector are 1.46VDC?
Ic of the NPN 9-2.49= 6.51VDC, 6.51VDC/91K=.0715ma
collector voltage drop of PNP .0715ma x 20K= 1.43VDC close to measured could be due to tolerances of the resistors
Both Ics(collector currents) are the same as they should be
So next NPN B to E drop =1.93-1.61= .32VDC
PNP E to B 1.61-1.46= .15VDC
PNP B and C both 1.46
PNP E to C .15VDC
Looks like both transistors in the circuit are biased more to saturation(higher gain) AND the series connection and no "current paths" except via the collector resistors(why I checked the Ics and voltages drops with Ohms law to make sure they matched) I guess they settle in at stable DC points. So hfe and base to collector resistors are something top be aware of.
Thanks for the voltage readings.
Q1 both the base and collector are 1.46VDC?
Ic of the NPN 9-2.49= 6.51VDC, 6.51VDC/91K=.0715ma
collector voltage drop of PNP .0715ma x 20K= 1.43VDC close to measured could be due to tolerances of the resistors
Both Ics(collector currents) are the same as they should be
So next NPN B to E drop =1.93-1.61= .32VDC
PNP E to B 1.61-1.46= .15VDC
PNP B and C both 1.46
PNP E to C .15VDC
Looks like both transistors in the circuit are biased more to saturation(higher gain) AND the series connection and no "current paths" except via the collector resistors(why I checked the Ics and voltages drops with Ohms law to make sure they matched) I guess they settle in at stable DC points. So hfe and base to collector resistors are something top be aware of.
Thanks for the voltage readings.
- Paul Marossy
- Breadboard Brother
Information
I built that Barge Concepts "clone" of the Harmonic Perculator for someone. I thought it was a pretty cool sounding thing.
- DougH
- Transistor Tuner
That clip sounds pretty good, pretty typical of the sounds I've gotten on the breadboard and with the Brick. Seems more bassy but IIRC I was still using .1u coupling caps in the Brick. I'll have to breadboard this latest schem and see how it sounds.theblackman wrote:https://cgi.ebay.com.au/Boutique-qualit ... 7C294%3A50
i wonder what diodes this guy is using his one sounds pretty good from the demo.
"You have just tubescreamered or fuzzfaced yourself " -polarbearfx
- RnFR
- Old Solderhand
Information
yes, i'd like to know as well!JJ Gabor wrote:Any word on the forward voltages on the 1n695s ?
"You've converted me to Cubic thinking. Where do I sign up for the newsletter? I need to learn more about how I can break free from ONEism Death Math." - Soulsonic
Blog-APOCALYPSE AUDIO
Blog-APOCALYPSE AUDIO
Unless you were asking for actual measured values,
http://www.datasheetarchive.com/1N695-datasheet.html
Here is the link to the datasheet;DougH wrote:I noticed that the 1n695 datasheet indicates a 1.0 fwd voltage drop @100ma and .5v @ 10ma.
http://www.datasheetarchive.com/1N695-datasheet.html
The Freestompboxes Forum search function is soo great, use the search function..., the S E A R C H function.
- RnFR
- Old Solderhand
Information
well, it lists almost every Ge diode on the sheet as having a 1.0 drop. even 1n34a's and 1n60's. now as far as i know, that's not accurate. i have some 1n66's and those are definitely not at 1.0 either.
"You've converted me to Cubic thinking. Where do I sign up for the newsletter? I need to learn more about how I can break free from ONEism Death Math." - Soulsonic
Blog-APOCALYPSE AUDIO
Blog-APOCALYPSE AUDIO
- theblackman
- Resistor Ronker
- DougH
- Transistor Tuner
I breadboarded JJ's schematic last night and it sounds great. I wrote it up in the perc thread at diystomp (I'm tired of typing). The 1n695's sound great, better then 1n34a's even though the fwd voltages measure the same, .223v.
"You have just tubescreamered or fuzzfaced yourself " -polarbearfx
- JOHNO
- Cap Cooler
I tried my hand at this one again last night. This time i built the npn version but it sounds all farty like the pnp npn version I built. I'll try two ge diodes in parallel on each side.
Must be the Knee then.DougH wrote:The 1n695's sound great, better then 1n34a's even though the fwd voltages measure the same, .223v.
The Freestompboxes Forum search function is soo great, use the search function..., the S E A R C H function.