univox ec80a tape echo questions

[p1_ind]

I got a univox ec80a tape echo last week and after finally tracking down tape cartridges the output seems a little low and also the echo repeat control only seems to add uncontrollable feedback into the signal. I don't know if that is its normal operation or not.

If anyone has a schematic it would be helpful because the only one that I have seen online was at univox.org and the values and lettering on the schematic are not readable.

Thanks,
Adam

[petemoore]

I had a Univox Tape echo unit that my bro somehow fixed wayy back when...IIRC the schematic was pasted on the inside somewhere???
 werth a look anyway...alot of stuff in one fo these units to get right...have the heads ever been inspected?

[p1_ind]

the heads are working fine and the echo is working but the overall volume of the effect only reaches just under unity gain and the echo repeat knob only brings feedback into the signal.

I looked everywhere on the case and inside and it has no schematic.

Adam

[Mark Hammer]

A couple of things to consider.  Forgive me if I underestimate your competence, but since tape knowledge seems to have fallen by the wayside for many who grew up in the CD era, it is not unreasonable to assume that the tape folklore hasn't filtered down to you....unless you're an old fart like me.

a) You can make you're own tape loops, and I imagine many of the tape cartridges floating around probably are homebrews.  The tape,however, has a recordable side and a less than recordable side.  The dull side should be in contact with the heads.  You can still get a recorded signal out of the other side, but what you hear is he magnetic imprint left going through the acetate backing and sensed through the acetate backing.

On the other side of the coin, these babies have not been in production for a looooong time, and if you have an original loop there is a good chance some fresh tape might be needed.  Bear inmind that tape loops undergo considerably more usage than conventional open-reel tape and there are only so many times you can drag the tape through the transport mechanism without wearing off some of the recording medium.  Depending on the cartridge format (I *think* Univox used something like an 8-track tape) it may be harder or easier to score suitable tape and wind your own.

b) "Working" and aligned are two different things. Tape heads and tape need to make flawless contact with each other.  If the tape head is not standing perfectly straight up and down, and vertical from side to side, what it leaves on the tape will be dramatically attenuated, both in level and bandwidth.  I would imagine the number of stereo repair places able to align heads these days is severely reduced in an era of digital minirecorders and throwaway consumer electronics.

[Mike Nichting]

Is the tape new???  If not I can tell you where to get a new one that is perfect for them~!!  I would not recomend using the old ones or a N.O.S tape.
I turned analogman (Mike) onto them. Let me know~!!

Mike N.

[BillyJ]

If you email me I can send you the schematic.
& hey Mike I'd love to know where to get some tapes too if you would email me that would fantastico!!

[BillyJ]

Found the link it is on this page:
http://www.univox.org/schematics.html

[p1_ind]

The tape is a new tape from Dictaphone (part number 0645180) slightly modified so the erase head will fit.
The heads seem to be fine nothing looks to be out of adjustment and the signal of the echo coming from the heads is just as loud as the straight signal going through the effect.  It is just the total volume only reaches unity gain and the echo repeat knob just introduces feedback into the signal.

Adam

[tiges_ tendres]

I know this is old, but I am about to resseurect one of these EC-80s myself.  I have the tape cartridge, and was wondering if anyone was had tips on aligning the heads. 

I was told this machine didnt work, but almost every single one of these machines seems to have the same problem.  The motors all run, but it seems the tape alignment is the issue. 

As far as the footswitch goes, does anyone know if you HAVE to have a footswitch to make it work, or whether thats optional.  I have an old bespeco latcher somewhere that should suffice.

so if someone can help me get this running, I would happily trade your skills for a few of unboxed circuits I have laying around.

[donald stringer]

I have been spying one of these out in the local music store. It works sort of, you can hear the tape turning but no echoe. He wants 50.00 for it as is but I have been hesitant as much I want to get that tape echoe sound in the chain. But I have read to many negative feedbacks about this particular model.

[p1_ind]

I got rid of mine a while back but I did fix the volume problems by recapping it.  When they are working good they sound great but they seem to me to be very temperamental.  You have to get the tape in there just right and hope that as the tape runs that it doesn't get any slack in it and move away from the heads.  Another down side is that it is hard to find good tapes for.

Maybe you will get lucky and have good luck with it because like I said when they do work good they sound great.  A great mod is to change the delay time pot to get longer delays.

I don't have any insight on the head alignment because I didn't try adjusting them on my unit.

Good luck,
Adam

[tiges_ tendres]

well, sure enough it sounds awesome.  I had a few problems, but I have a few tips for people for getting it working.

Like has been previously mentioned, the felt behind the tape is important.  My unit passes sound no problem, the motor turns and it turns the capstan, but the tape doesnt pass over the heads.

there is a plastic contraption inside that holds the cassette in place.  I removed that so I could get the tape closer to the heads.  What I found was that when you pressed the tape up to the heads, you could hear the echo!  However, obviously with nothing to hold the tape in place, its kind of hard to get a good sample!

to get it to work properly is pretty tough, but I got it going.  the important thing is to make sure that the tape makes good contact with both heads evenly, otherwise it will just keep playing back the same thing over and over, and wont record new stuff! 

There are also three trim pots inside.  One effects the speed at which the motor turns (a long with the delay time knob) another one controls the repeats (in conjunction with the repeats knob), and the other one, I'm not sure!   I managed to cause some runaway delay!

even though I barely got it working, whe I did, it was magificent!!!
I tried to shim up the tape by putting some sponge under the tape, but it was causing too much friction, and the motor stopped.  I have some felt somewhere I'm sure will work.

I will report some more findings!