[sdiy] Passive Ring Modulator

[Steve Begin]

Cynthia, on mouser.com I found this

http://www.mouser.com/index.cfm?handler=productsearch._listproductsearch&pre
cision=All&searchtype=starts+with&criteria=tl028&searchby=PartNumber&x=18&y=
10

I'm thinking maybe it's the same as the one in Ian's circuits, and it seems
very reasonably priced.  I figured I could get shiny new matching
transformers and go from there.  

I was hoping that since it was a passive circuit I'd have a fairly low
chance of blowing anything up, but you are right, maybe I should bring some
broken junk out of retirement to make sure nothing really bad happens when I
connect everything :)

I'm also really pleased with all the responses I've gotten, surprised too to
see Juergen Haible on the list (I've spent a fair bit of time admiring the
stuff on your site).  I'll try asking for help at a repair store, I fix
computers for a job and I agree that any sort of friendly human interaction
is a real nice break from errors popping up and blue screens. 

> Steve Begin



-----Original Message-----
From: Cynthia Webster [mailto:cynthia.webster at gte.net]
Sent: Tuesday, July 16, 2002 2:45 PM
To: Steve Begin
Subject: Re: [sdiy] Passive Ring Modulator



> All the talk of fets and opamps is over my head (hopefully I'll catch on
> eventually).  At this point I'd probably rather take the approach I'm most
> likely to understand over the cleanest or easiest approach. :)
> 

Hi Steve! 

I've been interested in this circuit too
 so it was very nice to see your interest and all the responses.

I'd start with Ken Stone's suggestion of gutting some cheapie transistor
radios for their X-formers and just start fiddling!

If the diodes are clear or really tiny don't use them
if the diodes are ceramic material and the size of a small pea
that's what you want.  Try the local electronics repair shop and talk with
the tech of you can get past the receptionist.
They;re usually grateful for any frindly visits from out of the blue!
(how would ypu like to stare as busted VCRs on a sloppy bench all day
"Gad - Look! A real-live human being!"  :)

Ideally get two identical transistor radios (eBay to the rescue)?
You could probably get a dozen for twenty-bucks from Singapore or sumthin'?

For experimentation, perhaps an almost disposable sound source so you won't
blow-up your prized somethingorother.  hey? How about using the remaining
transistor radios as inputs?

Cheers!

Cynthia






> Steve Begin
> 
> 
> 
> -----Original Message-----
> From: Terrence McWee [mailto:mcwee at m-net.arbornet.org]
> Sent: Sunday, July 14, 2002 12:51 PM
> To: ian
> Cc: Steve Begin
> Subject: Re: [sdiy] Passive Ring Modulator
> 
> 
> Steve & Ian,
> 
> I'm yet another dreadfully newbie SDIYer, so please bear with my dumb
> questions.
> 
> I'm getting pretty hyped up on this passive ring mod, and note that the
> design calls for "Four (4) diodes GE45A or equivalent."  What,
> precisely, constitutes a suitable equivalent to this?  I can't make
> heads/tails of that ID number.
> 
> Thanks,
> T.M.
> 
> On Friday, July 12, 2002, at 12:55  PM, ian wrote:
> 
>> Hi Steve,
>> I have a boxful of ringmods much like this sitting on my desk right
>> now! I
>> haven't had a chance to try them out yet, but other people who have
>> tried
>> them say they sound great. The design I have was given to me by a
>> colleague, and it comes from the Amateur Radio Relay League handbook. It
>> differs slightly from the one on sonicstate, as it has two diode rings,
>> which is supposed to provide better carrier rejection than the single
>> diode ring design. As for the transformers, the ringmods I have use one
>> from Mouser, marked TL028 down one side and 0109S down the other.
>> Ian
>> 
>> 
>> On Fri, 12 Jul 2002, Steve Begin wrote:
>> 
>>> Hi, I'm new to the list, not new to analog (am I gonna get in trouble
>>> if I
>>> spell it like that?)
>>> gear, but fairly inexperienced when it comes to circuitry.
>>> 
>>> I've got a question, has anybody had any experience with a passive ring
>>> modulator design like this one?
>>> http://www.sonicstate.com/synthfool/ringmod.html
>>> 
>>> I'm interested in it since it looks very easy to make and cheap and if
>>> it
>>> doesn't work as well as other designs it doesn't bother me that much.
>>> However,  I guess the stancor a-4713 driver transformers are no longer
>>> in
>>> production and I can't seem to find anything information on them at
>>> all, let
>>> alone a reference to a part I could use as a substitute.
>>> I'd really appreciate it if somebody could give me any direction at all
>>> here.
>>> 
>>> The other thing I was wondering about (and I'm sure it's probably
>>> painfully
>>> obvious to a lot of you) was half or full normalled patch bays.  When
>>> you
>>> split a signal doesn't it affect the impedance or something along those
>>> lines?  I thought it would be a bad thing to do but I haven't seen
>>> anybody
>>> mention any problems with that.
>>> How about combining signals without a mixer?  I'm almost positive you
>>> get
>>> problems doing that.
>>> 
>>> Thanks!
>>> 
>>>> Steve Begin
>>>> 
>>>> 
>>>> 
>>> 
>> 
>> 
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