Echoplex EP-2 won't record!

[jakenold]

Hi all,

I've bought an Echoplex EP-2 from a guy on eBay, claming it worked, only to find out it didn't. Tough luck.

The unit had some problems. It was really ugly inside, so I cleaned it out. Components measured good, but the engine was dragging the smallest thread-wheel against the chassis. So I tightened one of the screws for the engine and voila - it runs super smooth!

Now my problems are these:

The unit won't record. It can play back what is on the tape fine, but it never erases or records anything. All the tubes light up fine, and I don't expect them to be faulty, as it can both play back what is on the tape, and I can hear my guitar too.

Does anyone have an idea as to what is wrong? Does anyone have a schematic for the EP-2?

I'm buying some new tubes for the unit, just in case.

Thanks!

Jake

[Regis]

Hi Jake,

Can't say why it doesn't record, but check out my echoplex page, there are links for schematics and other stuff you can use for PD.

I recently aquired an EP-2 that a guy gave me, but haven't had time to look it over. In fact I'm not even sure it works.

Good Luck,

regis

[Wakculloch]

Sounds like the bias oscillator isn't oscillating.
Check the oscillator valve, the coil, and the biasing resistors in this stage.

[jakenold]

Hey Regis,

Yeah, I've checked out your site both before and after buying this unit. It's been a great help already, and very much appreciated! I found the EP-2 schematic elsewhere. If you do not have it on your site, I can mail it to you. Might as well save the 20$ if one doesn't need a hard copy anyways.

We can be repair-buddies! I'm going to try with some different tubes later on, and try it with a scope. It uses two 6EU7 valves, which is made in the Reflector-factory in Russia under the Sovtek-brand, and a single 6C4 valve which is obsolete, but still available in limited quantities from old stocks.

My unit runs perfect now, all I got to find out is how to get it to record and play what I recorded. It seems like it's stuck in S.O.S.-mode, with the record function disabled. That might be where I should look first.

Kind regards, Jake

[jakenold]

Sounds like the bias oscillator isn't oscillating.
Check the oscillator valve, the coil, and the biasing resistors in this stage.

Thanks for your responce Alan.

This was something I was thinking about as well. It just wasn't something I would look into, since the unit apparrently worked like a charm before the seller sent it to me. It wasn't banged up or anything when it arrived here (cudos USPS - much better than the Danish Post here in Denmark).

I know my way around most audio and guitar electronics, but I am sadly not an EE, but rather an economics and computer science student. Where should I look? What should I look for?

Thanks in advance!

Kind regards, Jake

[jakenold]

Wow, this was an pretty embarrassing.

I'm in Denmark, and we use 230V, so I had to use a step-down transformer. Apparrently, the one I had couldn't supply enough power for the Echoplex. I bought a new 600 Watt model, and the device works like a charm now!

Thanks for all your time, I definitely learned more than just remember to supply enough power!

Jake

[jakenold]

Just one last question:

Say I want to replace the tape in the machine with a new cartridge from Mr. Battle himself, how do I go about doing that now that I live in Denmark?

Is there a way to contact him or his son-in-law, now that I'm from overseas? If that is impossible, I would have to give Mike Fuller money

Jake

[Regis]

Just one last question:

Say I want to replace the tape in the machine with a new cartridge from Mr. Battle himself, how do I go about doing that now that I live in Denmark?

Is there a way to contact him or his son-in-law, now that I'm from overseas? If that is impossible, I would have to give Mike Fuller money

Jake

Someone is selling the Fuller tapes on Ebay right now for $31.00. The Battle people also sell them on ebay, do a search for echoplex tape. They give a snail mail address only on their webpage, without any prices.

While we are on the subject, I would recommend anyone with a vintage echoplex to buy several new tapes right now. I get the impression that Mike Battle, or his son or whomever is running that operation is fixing to give it up. Mike Fuller doesn't like to sell his tapes to anyone that doesn't have a TTE. So if the supply of Plex tape cartridges dries up and you don't have one, instead of a nice vintage delay device you'll have a nice doorstop on your hands.

The cartridges can be refilled if you have them and having two or three on hand guarantees you'll be able to use your plex until the end of time.

[stokes]

Try www.loop-master.com they do tape rewinding for the Echoplex.

[Enzo]

Antique Electronic Supply sells them. stock number: P-ECH-1-TP $36.50

www.tubesandmore.com

[jakenold]

Cool.

My local music store sells the Fulltone-tapes for 50$, which is about the same as it will cost me to get a Mike Battle-tape here, so I'll buy the Battle-one, just for kicks.

Jake

[Mark Black]

Here's another approach -

Buy a reel of tape from these guys:
http://www.cartguys.com/ctr_prices.htm#anchor973579
(Scroll down to "Echoplex-850X")

You get 2100 feet of the lubricated style tape required by endless loop cartridges like the Echoplex (or 8-track, which I used to buy at Radio Shack in blank cartridge form for this use. Alas no more...). Probably enough for a lifetime of refills.

Get a 1/4" splicing kit from these guys:
http://www.splicit.com/splicing_kits.html
(or someone else you can find online).

Take a look at this for some tips on correct splicing:
http://www.prosoundweb.com/recording...dit_11_1.shtml

You may be able to simply cut the existing tape and splice on the new one (making sure the oxide side is matched), then pull through (in the normal direction of travel) until the new tape comes out the other end. Then splice the new tape to itself with the correct external loop length. I don't remember whether this method works well but it should.

Otherwise, for custom tape lengths or to replace badly mangled or jammed tapes...

Make a jig which will mount the reels from your existing tape cartridge at exactly the same distance from reel to reel as the cartridge itself and allow you to spin it from a center point. Could be as simple as a piece of plywood with a couple screws to mount the reels and a lag-bolt from the other side as a handle for hand-spinning. Don't make the wraps very tight.

Make careful note of the orientation of the tape in your existing cartridge (drawings help) and how long a loop is hanging out. Make sure to note the orientation of the oxide side of the tape (should be "out" as I remember). Then pull the cover off your cartridge to access the tape & reels. After that...

Now here's where you have a couple choices. You could cut the existing tape and pull it out of the cartridge (in the normal direction of travel) while measuring so you can duplicate the length (assuming it's not bound up). Or you could measure the thickness of the tape pack with calipers (or your calibrated eyeball), yank it out and discard it, and wrap the new tape to approximate the same thickness.

Or if you can determine the IPS speed at which the tape runs you could make custom-length/time loops.

If I remember correctly I used to use the tape cartridge itself and wrap loops around the rollers slowly & painstakingly using the thickness method to build up a tape pack. Either way one of the keys is to make the loops relatively loose. Not real loose but not tight either or the tape may bind.

Maybe some other old fart cheap bugger (like myself) can weigh in here...

Good luck!

[Enzo]

Well i fit that description, thank you. I have refilled these tape cartridges before. I used to be in radio, long long ago, and we used lube backed tape for our "carts" which for all the world wre like 8-track cratridges without the roller inside. It has been a while, But seems to me I did exactly as you propose.

And yes, don't roll it too tight. I don't think the length is critical, it will take up slack on its own, so close is good enough on slack. As to how long to make the tape overall, unless you are prerecording stuff to play against, I don't think it matters. if your tape is too few turns, then the same tape flys by over and over too quickly and it wears out fast. But on the other hand there are commercial tape echoes with very short tape loops.

[stokes]

"You may be able to simply cut the existing tape and splice on the new one (making sure the oxide side is matched), then pull through (in the normal direction of travel) until the new tape comes out the other end. Then splice the new tape to itself with the correct external loop length. I don't remember whether this method works well but it should."
I did a refurb on an Echoplex and wound a new tape just this way.I read how to do it this way on someones site,but I dont recall where,if you do a search on Echoplex tape you will find it.

[rockinrendell]

this isnt exactly true. if one does not have an original echoplex cartridge you can modify an 8-track cartridge so it pulls properly. i tested my unit with an 8-track to see if it would work and it does, only the way it pulls out of the stock cart it didnt pull smoothly so one would have to be modified for that in a pinch or you can add a spring loaded idler pully and use a loop. but these would be only cuz you cant get the right carts. food for thought. ive even thought about rigging it up with a solonoid kill switch so units is on and passes signal when not being used and kicked on when you want to use for certain song. would really preserve tape life big time.