Calling maczrool: Remote Display Extender Problem

Posted by: tfabris

Calling maczrool: Remote Display Extender Problem - 10/08/2017 20:39

Hey, Stu!

I finally got a chance to use the Empeg Remote Display Extender that I bought a few years ago. I am having a problem with it, and I'm wondering if you know what's up.

The problem is:

After it's all installed and connected on the bench with the ribbon cable, power up the player. Display lights up and works, and the correct image picture appears on the VFD display. Player seems to work normally for the most part: it loads up songs and plays them.

However, there are the following things which do not work:
- The buttons and knob do not produce any results. Pressing buttons and turning the knob does nothing.
- The illuminated button kit that I have installed on the display does not illuminate.
- IR input does not work.

All of those things were working immediately prior to the installation of the remote display extender.

Do you have any idea which component or connection I should be checking at this point?

Thanks!

PS: Tried to use the "contact us" form at the Eutronix web site first. The form is currently nonfunctional. It asks for a CAPTCHA, but there is no image for it.

PPS: If anyone else on the board recognizes these symptoms, please let me know if you have any ideas.
Posted by: mlord

Re: Calling maczrool: Remote Display Extender Problem - 11/08/2017 10:54

Ah.. another item for which schematics don't seem to have been published.
Posted by: mlord

Re: Calling maczrool: Remote Display Extender Problem - 11/08/2017 11:23

Originally Posted By: tfabris
Tried to use the "contact us" form at the Eutronix web site first. The form is currently nonfunctional. It asks for a CAPTCHA, but there is no image for it.


You could just email him directly. I'll PM you the last good address I had.

As for the fault.. it most likely revolves around pin-10 "IRRX" of the displayboard ribbon cable. Either where the displayboard connects to the extender, or where the other half of the extender connects to the empeg itself. So perhaps do your best to trace that wire along those paths for clues.
Posted by: maczrool

Re: Calling maczrool: Remote Display Extender Problem - 12/08/2017 12:34

Hey Tony,

Message received. The web form was removed to correct a spamming issue and reinstalled but haven't had the chance to fix it.

I sent you an e-mail with the following:

The line driver ICs are known to give out sometimes from static discharge. There isn't much in between transmitter board and receiver boards for the buttons so if these connections all have continuity I would guess a bad IC (MAX3237EAI+). The control line of the display which controls the buttons and remote run through pin 6 of the display connectors. On the transmitter board, the control signal goes through pin 17 and 12 of IC34, through filter C107 pins 6 and 15 to DB-25 pin 13. On the receiver it goes through DB-25 pin 13 to filter C116 pins 15 and 6 to IC35 pins 8 and 15 and back to display connector 6. Also make sure R51 on the TX board is populated and not R52. Should be since these were all tested before shipping.

Let us know what you find.
Stu
Posted by: tfabris

Re: Calling maczrool: Remote Display Extender Problem - 12/08/2017 17:09

Mark and Stu,

Thanks so much for your help! This is exactly the information I was looking for, and I am going to start working on diagnosing the issue right now.

In case this additional information is helpful, here's what I've done so far:

- Temporarily reconnected the display board directly to the player to confirm it still works: Confirmed, the display board still works, buttons light up and everything.

- Tried both the backward-facing connector and the downward-facing connector on the display extender, to rule out a connector problem. Both connector paths reproduce the issue.

- When connected via the display extender, noticed an additional symptom of the problem that I hadn't mentioned before: When the player boots, the standby LED blinks once very briefly at the very beginning of startup, instead of slowly pulsing during the entire boot process like it normally does. At the same time, the custom button LEDs also blink once very briefly and faintly, then go dark and stay dark.

Okay, now I'm going to go get the multitester and start tracing stuff based on your recommendations.

Thanks again!
Posted by: tfabris

Re: Calling maczrool: Remote Display Extender Problem - 12/08/2017 18:08

Stupid question:

The extender board does not require an additional power supply, correct? It should work as expected with the parts supplied in the box and power applied to the player only, correct?

There was a note on the instructions about how one could apply additional power to the extender board if you were going for longer cable runs. But the additional power isn't needed if you're only using the ribbon cable supplied in the box, correct?

Thanks!
Posted by: mlord

Re: Calling maczrool: Remote Display Extender Problem - 12/08/2017 18:14

Correct. The extender leeches power from the empeg over the ribbon cables. But there are onboard jumpers which can be changed if one wants to provide it with separate power. Double check that those jumpers are set correctly for leeching from the empeg.

Originally Posted By: Instructions
Other Features
Normally, power for the display comes from the Empeg/RioCar itself and is carried over the ribbon cable. The receiver board
is equipped with on board voltage regulators that will allow the use of an external 12-volt power source to operate the
display. This allows for much longer cable runs to be used.
Should you need to employ this option, simply move the two jumpers on the receiver board to the position closest to the
labeling “PL16” and “PL17” respectively. This removes the power from the Empeg/RioCar from the receiver outputs and
places the regulators in circuit. Next, attach a proper connector to the two pin right angle header on the left side of the
receiver board, assuring that ‘–‘ is on the right pin and ‘+’ is on the left.

Posted by: tfabris

Re: Calling maczrool: Remote Display Extender Problem - 12/08/2017 18:40

Issue solved!

Did:
- Confirmed resistor on TX board was in R51 not R52 (it was already good).
- Reflow solder on all ribbon connector pins on TX board.
- Reflow solder on all chip pins on TX board, including MAX3237EAI.

Did not solve problem.

Then Did:
- Reflow solder on all ribbon connector pins for the small ribbon connector on the RX board.
- Reflow solder on pins for IC38, IC39, IC35 (MAX3241ECAI) and 4420P-601 on the RX board.

It works correctly now!

Thanks, guys!
Posted by: mlord

Re: Calling maczrool: Remote Display Extender Problem - 12/08/2017 22:15

Well done, Tony!
Posted by: tfabris

Re: Calling maczrool: Remote Display Extender Problem - 13/08/2017 16:11

smile Thanks for your help!