So its been a while since I've been here.  I haven't really been playing too much guitar, and my electronics interests have moved away from stompboxes towards stuff that I can understand better...

but I found this lying around my house, and thought you guys might be interested.  Its a manual (or at least the interesting pages) from a radio shack kit.

edit: the pictures lost a lot when uploaded to photobucket.  If anyone is interested, can somebody either give me access to or post this to the gallery for me?  Is that even still around?  It really has been a while since I've been here lol

Wow, to think that Radio Shack once carried SAD1024 BBDs.  Those days are surely gone!

I have some old Radio Shack circuit books with circuits using the SAD1024 as they used to carry them. Ah the times...

Andrew

Quote from: mdh on December 17, 2007, 12:09:37 AM
Wow, to think that Radio Shack once carried SAD1024 BBDs.  Those days are surely gone!

yeah. they even had a fair bit of circuitry as recently as the late eighties!
now they pretty much cater to the cellphone/ipod/camera/laptop/alarm clock crowd, just like every electroncis store. save for a few "mixed bag" baggies of resistors in the corner or whatever.

One on the bay:
(sans parts)

http://cgi.ebay.com/Original-Electronic-Reverb-KIT-Archer-Radio-Shack-1980_W0QQitemZ130183160232QQihZ003QQcategoryZ308QQcmdZViewItem

Does anybody think that this is worth building?  Or are there better designs available?

The question is, how does it sound? If it's something like the Arion SAD-1, I think it would be worth it. But that SAD1024 IC chip is going to be rather expensive...

You'd be better off with "real" spring reverb with tube...
Just my .02

The younger folk here have little idea about how cool Radio Shack used to be.  It always seemed there was at least one cool chip that would be introduced each year as part of their stable.  One year I think it was the MN3001.  Another it was the SAD1024 (and the kit shown looks very much like the datasheet accompanying the SAD1024, if memory serves).  Other years, the hip chip was the Signetics compander (570, then later the 572), the TI SN76477 sound effects chip, the Mostek MK50240 top octave divider used in so many early keyboard synths (and PAiA projects), the MM5837 noise generator chip, and finally the voice-recorder chips that have become the staple of numerous DIY loopers.  I'm not THAT old, but I imagine at one time hobbyists thrilled to see 555 timers, and 556 dual timers, in their local Shack.

The schematic for the project shown is essentially a flanger/chorus type unit with variable initial delay.  When the modulation is reduced to zero depth, the delay control allows it to function like a sort of "reverb", though it is hard to imagine it being anything other than boxey-sounding, given the delay times attainable by the circuit.  The most interesting thing is probably the LFO circuit, which is similar to the one used in the Phase 90, but has a pair of clipping diodes and series resistor in the feedback loop of the op-amp, suggesting that it may provide somesoft clipping of the LFO waveform, yielding something approximating a sine wave rather than the usual more linear triangle.

Build one if you want to learn what BBD clock noise sounds like.   

heh, heh!

Yes, in the absence of companding, and very much lowpass filtering, and in the presence of variable delay range, I imagine it is not the quietest unit in the world.

I think I actually had one of these back in the distant past...  I don't recall keeping it, though, when tells me it might have been disappointing (probably exactly due to the BBD noise mentioned here).  I'll check with my parents, though, to see if it is still piled in their basement somewhere. (The packrat gene did not skip a generation -- lol).

Radio Shack *was* cool in the past -- although I didn't appreciate some of their predatory behavior toward other electronic suppliers.  They absorbed a lot of smaller companies and eventually choked down the breadth and depth of what they offered.  If memory serves me correctly, RS was reasonably cool in the late 60's/early 70's, but by the late 70's started to lose that cool as they got more interested in selling Computers, Stereos, Televisions, and VCRs than in selling kits, parts, and the like.

Back to the subject at hand (not to hijack) -- the BBD chip is going to be the largest expense if you want to build one of these things.  Given the various issues, I don't know if I'd recommend it unless you have a burning desire to do so (and funds aren't an issue).

I have one of these in a homemade case I pickup years ago.  I keep planning to set it up as a test unit for SAD1024 ICs (with a ZIFF socket) but I haven't yet.
FWIW I picked up 4 NOS SAD1024 in Radio Shack packaging along with a bunch of other ICs at a hamfest this past summer for $5.

Any chance of a good quality scan of the reverb schematic?  It would definitely help with my tester build.

Hey I've got one of those too!!!  Along with the drum machine (using the noise generator chip I believe) and an six digit frequency counter that I later sold to a friend.

I had someone send me a scan of the manual (in french) about two years ago because I was going to revive the thing.  The downer was that he only had pages 1-14 (the schematic is on pg15) so I too would like a hi-res scan if available.  As I remember it wasn't that noisy but the reverb wasn't hot by today's standards by any mans.  Since it was line level input I only tested it between a tape deck and my stereo input, I never got around to building a preamp for it.

I would think a dual microamp (tonepad) would do it some good as well.

Cheers

Do understand that there were a lot of things in the late 70's that were called "reverb" but were nothing of the sort.  Typically, these were very short delays, whose delay-time was not long enough to provide an audible repeat echo.  People were just tickled pink to get anything that sounded like an ambient space, even if that "ambient space" sounded like yelling into a tomato juice tin.

Eventually, tastes were refined and people started to notice the difference between short, highly resonant delays, and real reverb, and the labelling/legending started to change.

I must have started going to Radio Shack right after these kits were discontinued, though I do remember them selling SAD1024s! I was a Radio Shack addict from about 12 years old on! I'm now the proud owner of 2 Radio Shack/Moog MG-1 synths, several original PZM mics and of course, the Electronic Reverb!

The Electronic Reverb I have is the non-kit one that the sold in the 90's for $39, if I recall correctly. It's a 75ms analog delay based on a Panasonic MN? chip, I think. It's probably of better sound quality than the kit we're talking about here, and even so, it's a pretty lightweight contender for a cool delay/reverb, if you ask me. What I love about my Electronic Reverb is the ability to overdrive the hell out of it. I used to crank the microphone gain (with my guitar plugged into it) and use the RCA line out to power a crappy stereo speaker! It was a great cheezy fuzztone. Put a smidge of slapback on it and it was a glorious noise.

Audio Damage make a great plug-in version of it. A fun trip down memory lane.



http://www.audiodamage.com/xgrades/product.php?pid=AD002U

Roger

This one goes to mainly to those old enough to remember the "Glory Days" of Radio Shack (Ok, anyone really).
Radio Shack had another reverb kit back in the early 80's (81 - 83 or so I think).
It was different than this one.
I remember that it required a germanium diode (I remember I had trouble finding one) and had a double pot (stacked on top of one another).
I remember modding it by adding a resistor somewhere (near where the double pot was mounted) and taking the double pot and using 2 separate pots, mounting the whole thing inside a wah pedal. And those 2 pots, I had them turning in opposite directions.
Gave me some REALLY FREAKY sounds.

Anyway...I'm looking for this kit, schematics, pictures, or anything that would allow me to build another one of these.

I remember a friend of mine had a reverb unit like that for his stereo. I thought why on earth would someone want reverb on their stereo?!?  Then he turned it on and I remember it sounded pretty cool. Or so I thought at the time. That was a long time ago...ago...ago...

Quote from: Mark Hammer on December 17, 2007, 03:56:33 PM
People were just tickled pink to get anything that sounded like an ambient space, even if that "ambient space" sounded like yelling into a tomato juice tin.

Ahhh... the ambiance of tomato juice

Although this is an old thread, anyone looking for the manual (including schematic) for the Archer 277-132 Electronic Reverb project can find a PDF version here:

http://www.pmerecords.com/Docs/Archer_Electronic_Reverb.pdf

Back in 1980, I built this with the intention of using it on bass/guitar.  As others have said, it is somewhat noisy, especially with longer delay times.  The reverb quality is very metallic, as might be expected from simply adding regeneration to a single delay time.  The modulation section is interesting, though the delay times are far too long for flanging, and are best for chorus or double-tracking type sounds.  Specifications claim that the delay goes from 17 to 34 mS.

As I'm planning to use the SAD1024A chip for an A/DA flanger build, I fired mine up to make sure that the chip still works.  For some reason, however, I can't seem to get the BBD bias to stay put, so it's outputting a distorted signal.  It quickly passes through the "sweet spot", but won't stay there, and turns into distortion.  One of the trimpots nulls the clock signal, so that's not an issue.  I'm hoping that the problem is something other than the SAD1024, perhaps an old capacitor, diode, or whatever....