Continuing saga of the Profex cancer

Ken Fox · From: Nashville GA USA

Another fine example of a near mint condition unit that played right up to the bitter end with no low battery warning. I have replaced all components affected (3 transistors, 2 small 0.1uf caps, 3 each 22uf/25Volt caps, 10K resistor and a 1 meg resistor) except one IC and socket (on order from Mouser). Two plated thru holes were rotted out from acid as well causing the "Not a Profex 2 Card)" error message.

The only final warning was low volume!!!

Very typical of what I am seeing now with most of these units.

Randy Cordle · From: Illinois, USA

Hi Ken,
I had the exact same thing happen to a Peavey mixer that I owned. Corrosion on three circuit board traces killed one channel. Luckily I could bridge the traces and repair it easily. My board was just over a year old at the time.
Randy
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www.Bluestemstrings.com

Mike Brown · From: Meridian, Mississippi USA

What a lot of musicians did not realize when the programmable processors came to realization in the late '80's, early '90's is that these machines had to have "some" method of maintaining or holding memory. At that time, the method was by battery backup which was the latest and the greatest. These days, technology has advanced to using chips for backup, which is better as chips don't leak.

A word to the wise for Profex II, Profex, Transtube Fex and Tubefex owners. Have the battery checked by a tech about every 4 years so that it can be replaced before it begins to leak.

Ken will install his chip mod if you wish, or we can check and replace the battery while your unit is here at the factory.

Dave Potter · From: Texas

Donny Hinson · From: Glen Burnie, Md. U.S.A.

Undoubtedly, it was the cheaper way out. Originally found on computer motherboards, the soldered-in batteries mounted directly on the board would usually last 5-7 years, which was fine. That wasn't a problem on computers, as their service life was limited by buss speed and type, and they'd normally be rendered obsolete in that time period. With amplifiers and such devices, though, service life was expected to be measured in decades, and the batteries weren't made to last that long.

Non-volatile RAM (the type which needs no power for memory retention) has become far cheaper in the past decade, so these types of problems will only be found on older devices, those which took advantage of the cheaper volatile RAM of the period.

Caveat emptor, as they say. Neutral

Jack Stoner · From: Kansas City, MO

Coming from someone who has been a computer tech, the Profex II design was "state of the art" when it was designed (must have been late 80's by the design). By today's standards or even standards of 1996 it was a "relic" and the newer designs either do not use a battery or use a battery that is user accessable and replaceable without having to take it apart.

The TubeFex/TransTubefex designs were obsolete when Peavey brought them out, compared to multi-effect processors by other companies, and basically used the "old technology" of the Profex II. From a user standpoint these units were very good and easy to program, but from an engineering view they were not "state of the art" devices and still used the same old technology batteries and battery backup.

The Peavey memory cards are in the same boat. They must have a battery to maintain the memory, although they do use the more modern "coin cell" type batteries. But, my wife has an early 90's (maybe late 80's) design Brother Embroidery machine that uses a memory card that is about the same size as current memory cards that are used in digital cameras and it does not require a battery to maintain the card's memory. So the technology was available for the memory cards.

David L. Donald · From: Koh Samui Island, Thailand

Well this prompted me to pop the top on the Tubefex.
I DID order Ken's kit a ways back, but had little
work space and time, and the back burner got put out.

I just saw this battery was JUST starting to leak,
not any serious damage the circuit board,
but enough to fuse the battery to the battery holder/contacts
and this was not kind when taking it out.
I HOPE the board survived adequately,
one contact did come up, and it's quite twisted now.

So another unit on the list for more extensive repairs,
and lord knows where Ken's upgrade kit got packed
during the last move... DRAT!
_________________
DLD, Chili farmer. Plus bananas and papaya too.

Real happiness has no strings attached.
But pedal steels have many!

Jack Stoner · From: Kansas City, MO

The battery is permanently connected to the "end holder contacts" that are soldered in the circuit board. There is no "battery holder" just the entire battery assembly.

David L. Donald · From: Koh Samui Island, Thailand

Well that wasn't obvious... I DO have a solder sucker.
_________________
DLD, Chili farmer. Plus bananas and papaya too.

Real happiness has no strings attached.
But pedal steels have many!

Donny Hinson · From: Glen Burnie, Md. U.S.A.

Jack's right, the batteries are actually welded to the holder, which is then wave-soldered into the board. Interestingly enough, some companies (back into the '70s) put user-accessible holders for coin-cell batteries in devices that required a battery for memory. This would have been the preferable (though slightly more expensive) alternative for Peavey, rather than relying on soldered-in batteries.

When you're producing thousands of products, cost savings of a dollar on each one become significant to the bean-counters (that now make decisions in every big company).

Ken Fox · From: Nashville GA USA

It is far better to wiggle the battery and break it off at the board rather than try a soldering iron! The just put in the new memory chip and reinitialize. You can do board damage pretty easy.

I did not post this to slam Peavey> I wanted to warn folks to look inside of their effects units before the damage is done. Unfortunately most I see now are damaged.

Mike Brown · From: Meridian, Mississippi USA

But there sure are alot of the Profex II's still in use. Like any product, spell automobile, maintainence is required. It was and still is a great product!

Rich Peterson · From: Moorhead, MN

Actually, two questions.

1. Are any steelers using the CT (Coil Tap) algorhythm to shape their sound? A powerful tool if you want to get single coil tone, but use a humbucker to control noise. I feel it is a powerful tool and would like to see it available perhaps in a stompbox.

2. Wouldn't we like to see Peavey bring out an updated version of the ProFex-TubeFex-TransTubeFex, either as a rackmount standalone, or as an enhancement of the Revalver software?

I'd buy a used laptop in order to have that on stage with me.

Ken Fox · From: Nashville GA USA

I totally agree, Mike! It is a great product, user friendly and a lot of quality sounds. I love to warm up any amp with one!!!

David L. Donald · From: Koh Samui Island, Thailand

Mike I agree I have two.

And Ken I certainly appreciate the info.
And I assumed the info was about best keeping a
good Peavey product running properly.

Historical perspective on style of design is usful,
but don't think that if it wasn't the latest and
greatest of a given date, that that makes it not
the right product for that date.
Latest and greatest is also
often times considerably MORE expensive too.

Good functionality and 'affordable' price are also
high considerations for purchases.

Now if I could just find the kit I got from you...
I knew exactly were it was till I mOVED house...
_________________
DLD, Chili farmer. Plus bananas and papaya too.

Real happiness has no strings attached.
But pedal steels have many!

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