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TubeFex Family - Version 2.0 EPROM Removal/Installation

Should questions or problems arise, feel free to contact Repair Assistance here at the factory 601-483-5365.

Ordering Version 2.0

Call parts (601-483-5365, ask for parts), or send e-mail to parts@peavey.com

If you're in Europe, send e-mail to Andy Holland at Peavey UK.

Customer Prices:
$49.99 TubeFex, TransTubeFex, or TransFexPro (please specify)
$19.99 PFC 10 (including stickers for labeling the unit)

Locating your unit's EPROM:

On all models (except the PFC-10), make sure you save any user data to a RAM card or MIDI storage device before proceeding. Initialize the unit by holding the DOWN and RIGHT cursors, applying power, and holding until the display prompts “memory initialized”. Note the orientation of pin one and the “notch” on the chip before removing it! Be sure to initialize the unit again after installation of the new part. We recommend this procedure be performed by an authorized service technician!

TubeFex: Remove two screws on the left and right sides, one screw on the top towards the right side of the display, one screw on the back panel. The EPROM is located in the middle of the circuit board, reference designator U506.

TransTubeFex: Note the top panel is in the shape of an inverted “U”. Remove three screws on the left and right sides. Remove three screws from the front panel, two of them are on the extreme right and left sides, the third is in between the up and down cursor buttons. Remove seven screws from the back panel: two each vertically on the left and right, three across the top. The EPROM is behind the cursor buttons, reference designator U506.

TransFex Pro 212S: From the back of the unit, first disconnect the speakers (remember yellow is hot, blue is not). Remove the A-C cord strain relief screw located on the left in front of the transformer. Remove one screw from the left and right sides directly under the chassis. Remove the four top screws, and slide the chassis out the back of the cabinet. The EPROM is on the front board behind the cursor buttons, reference designator U506.

PFC 10: Remove three screws from the right and left sides, three more smaller screws from the back panel. The bottom will come off with a bit of effort (it is tight). The EPROM is located at the right side of the board with the unit upside down and the front towards you.

Removal of EPROM:

Remove the chip from the socket carefully (pry a little between the chip and socket on one end, then on the other end, then the first end......until the chip comes out easily

Placement of version 2.0 EPROM:

Place EPROM into socket, making sure the notch in the end of the chip matches the notch in the end of the socket. (You can destroy the part if you put it in backwards.) Also make sure to get all the pins into their hole. Sometimes they end up on the outside (easy to see); sometimes they end up bending inwards and missing (harder to see). Pins can be gently straightened with needle nose pliers if need be. Again, we recommend this procedure be performed by an authorized service technician!

Initialize the unit by holding the DOWN and RIGHT cursors, applying power, and holding until the display prompts “memory initialized”.

Restore your presets via MIDI or RAM card, and PLAY!!!

NiCad Battery replacement with newer NiMH battery:

There is probably a NiCad battery in the unit that looks like a blue cylinder. This is used to hold the RAM data when powered down. When this gets old, it can stop holding a charge and cause loss of data. Even worse, it can leak and the acid can damage the circuit board. If you have an old one (5-10 years or more), it is strongly suggested that you replace it with a newer NiMH part (the ones we currently use are green).

Peavey part number is 70901721, list price (as of 12/06/02) is $14.02.
Call parts (601-483-5365, ask for parts), or send e-mail to parts@peavey.com
If you're in Europe, send e-mail to Andy Holland at Peavey UK.

The process would be:

save your data via MIDI or card
power down and remove the battery (it is soldered in)
[clean and/or repair board if there is acid damage]
put the new battery in
power up and leave on overnight
re-initialize the unit
restore data from MIDI or card

Battery removal/replacement with Simtek (was ZMD) nvSRAM:

There is a non-volatile SRAM chip that can replace both the regular SRAM and battery in the TF, TTF or TFP (even for the Session 2000 pedal steel amp - but NOT for the ProFex, ProFex II, or BassFex). The SRAM is the 28-pin socketed IC - slightly smaller than the EPROM, and with no sticker. It is a volatile RAM, so it needs the battery juice to hold its contents when the TF is powered down.

This new chip will remember its contents at power down via an EEPROM shadow (no battery!), so the big blue (or green) battery can be removed from the board.

NOTE: You have to backup your data before you do this! The RAM chip is where the patches and globals are stored, so when you replace the chip you will have to re-initialize and restore data.

The chip needs a little surface-mount 10K resistor soldered between pins 27 and 28 (to keep it happy at power up), but other than that, you just drop it in and unsolder the battery. (When reading the writing on the chip, pins 27 and 28 are on the top left at the very end.)

NOTE: it doesn't have to be a surface mount resistor, but it is a perfect physical fit. They're probably hard to get as a one-off, so a regular resistor can be tacked on with a higher ugly factor.

Peavey doesn't stock these parts currently - I brought some samples in to check out (my TransTubeFex and PC1600x are now battery-less), but I don't have a current project that needs that much nvRAM, so I doubt if I'll be able to bring them in for service purposes only.

The part is a Simtek STK16C88-WF45 - 32Kx8 Battery-backed SRAM replacement. Ken Fox has volunteered to be the middle man for delivering these parts (see below). He is buying small quantities and soldering the 10K SMT resistor. So after purchase, you replace the SRAM with the new nvSRAM and remove the battery. Remember, you have to backup your data before you do this! The RAM chip is where the patches and globals are stored, so when you replace the chip you will have to re-initialize and restore data.

To get a Simtek upgrade - Contact Ken Fox via e-mail to make sure he has a part available for you and get pricing/shipping info. Or check out his site here:
http://foxvintageamps.com/classic_green_006.htm