MOTM

In a message dated 00-06-15 23:20:54 EDT, you write:

<< I built one of these as a young teen and it worked great >>


ivan,
have you tried "digi-key" ?  also, a "surplus" place like "fair radio sales" 
might have something suitable.
( p.s. - ( and i mean this in the best way ) - you are a madman !  i built my 
first one of these diode bridge gizmo`s back in the late 60`s / early 70`s 
and used it with a test oscillator and other assorted inputs for a long time. 
 was one of the first bits of electro-junk i cobbled up from radio stuff i 
had as a ham radio operator. i don`t think it was very well balanced and it 
didn`t really sound like any rm i`ve had in a synth since then but it was 
great fun !
best,
dave v.

In a message dated 6/15/00 11:36:51 PM, davevosh@... writes:

<< p.s. - ( and i mean this in the best way ) - you are a madman !  >>

Thanks.... that's a compliment!  I used mine with a SWTPC function generator 
and an HP oscillator and it sounded GREAT!  Not sure why, but was just really 
well balanced.  Checked it on a scope and it was doing exactly what it was 
supposed to do with two sine waves going into it.  I've been checking around 
for similar transformers and haven't found what I'm looking for (but have 
been a customer of Fair Radio Sales for years).

Ivan

In a message dated 00-06-16 00:26:48 EDT, you write:

<< 
 Thanks.... that's a compliment!  I used mine with a SWTPC function generator 
 and an HP oscillator and it sounded GREAT!  Not sure why, but was just 
really 
 well balanced.  Checked it on a scope and it was doing exactly what it was 
 supposed to do with two sine waves going into it.  I've been checking around 
 for similar transformers and haven't found what I'm looking for (but have 
 been a customer of Fair Radio Sales for years).
  >>



ivan,
i used mine with an ancient hp oscillator  ( mine had a variable capacitor 
for tuning that was about 12" long. i unscrewed the metal top to the unit and 
bent it up a bit so that by vibrating it by hand, it affected the var. cap. 
and added vibrato /pitch bend to the oscillator output ), a simple bfo type 
sine gen. i built, a wheezy old vox jaguar organ and anything i was able to 
plug into a simple pre-amp like mike`s and guitars. great fun ! i always felt 
like a young stockhausen probing the depths. of course, everyone else had 
already done a lot of this stuff but at that time, i didn`t know that. plus, 
not knowing what was "supposed" to work versus "not supposed" to work was 
very liberating. i just tried every silly thing i could think of !
re : fair radio sales - i have bought the odd bit from them over the years. 
occasionally they have cool stuff at a very reasonable price.
best,
dave v.

hello all, hello ivan

just a couple of quick questions about the ring mod circuit

firstly - what sort of transformers are needed (i have a pile of balancing transformers around somewhere)

second - what sort of diodes 1N4148 for instance..?

cheers

paul b

Anyone here know of a good (available) substitute for the Stancor A-4713
driver transformers used in the classic ring modulator circuit (see attached)?

In a message dated 6/18/00 3:46:21 PM, vulture.squadron@... writes:

<<   just a couple of quick questions about the ring mod circuit >>

I'm enclosing the parts list which answers the questions, along with the JPG 
for anyone who missed it the first time around:
-------------------------------------------
Passive ring modulator

Parts needed:
Two (2) Stancor A-4713 driver transformer
Four (4) diodes GE45A or equivalent
Many small audio transformers will work to some extent.
The diodes must be germanium and not silicon types.