Can't access internal sound and performance patches

It sounds like you have accidentally set your Zoom 606 pedal to the "AL" patch. The "AL" patch is a special patch that allows you to access the pedal's internal settings and make adjustments.
To turn patches on, you will need to exit the "AL" patch and select a regular patch. Here's how to do it:

1. Press and hold the "Program" button until the display shows "AL."
2. Use the "Value" knob to select "P0."
3. Press and hold the "Program" button again until the display shows "P0."
4. Use the "Value" knob to select the desired patch.
5. Press the "Program" button to exit the patch selection screen.

Your pedal should now be in the patch you selected. You can use the "Value" knob to adjust the settings for the patch as desired.
If you are unable to access the patch selection screen, or if the pedal is not functioning properly, you may need to reset the pedal to its factory default settings. To do this, press and hold the "Program" and "Value" knobs simultaneously for about three seconds until the display shows "F0." This will reset the pedal to its default settings. You can then follow the steps above to select a patch and make any necessary adjustments.

There could be a few possible causes for this issue with your Yamaha DX7 synthesizer. Here are a few things you can try:

1. Check the connections: Make sure all connections between the battery, the synth, and any external devices are secure and in good working condition.
2. Re-initialize the synth: You can try re-initializing the synth by pressing and holding the "Data Entry/Memory" button while turning on the power. This will reset the synth to its default settings and may fix any issues with the presets.
3. Check the synth's memory: If the synth's memory is full or damaged, this could cause problems with the presets. You can try clearing the memory by pressing and holding the "Data Entry/Memory" button while turning on the power, then selecting the "Erase Memory" option when prompted.
4. Check the synth's firmware: It's possible that the synth's firmware could be causing issues with the presets. You can try updating the firmware to see if that resolves the problem.

It sounds like your ROM battery, which the ROM contains and stores the patches for the keyboard, has gone completely dead and your keyboard is dead in the water. However, if you can get a MIDI to USB converter and get the battery changed, then you can reload the patches back onto the keyboard.

I have worked on a Korg M1 Workstation and have had to replace the battery(CR2032) and then had to run a program called "MIDI-OX" which also gave me access to the patches needed in order to restore the keyboard to factory patch settings.

http://www.midiox.com/

Take a look at this AFTER you have gotten the battery replaced. I will tell you that replacing most batteries is a very intricate job as, the bottom of the keyboard has to be removed, as well as a lot of the internal boards. I had to draw a diagram and mark certain pieces so I would know where they went and in what order they have to be re-attached. My advice is take it to someone who works on electronics unless you want to DIY (not recommended) to get the battery replaced.

Hope this helps.

Open the unit CAREFULLY to avoid damaging cables between top and bottom. Inspect the defective keys. It may either be a broken part on the key OR the silicone rubber key contact carriers that can act as springs. Get repair parts from Yamaha America in California. Find number online and call the "parts department"

I'm not familiar with this kind of keyboard, but it is almost certainly that you have 2 parts (2 instruments) layered together. In this case a bass and a cymbal. This is a feature, not a malfunction of every multitimbral keyboard. Multitimbral means you can play more than one instrument at the same time. This is good as you can create some nice fat sounds, but put the wrong instruments together and you'll have the problem you're experiencing. My suggestion is that you read what the manual says about layering or mixing parts. There you should find instructions on how to turn one of the instruments off. You can also try to google the words "how to parts layer (or sound layer, or combine sounds) on the Yamaha S80". Good luck.

Given its age, this unit needs a little TLC. Units of that vintage used some capacitors that may have dried out a bit and need to be replaced. There are also op-amp ICs internally that may be defective. I would suggest a visit to a service shop that works on keyboards as not all do.

Keep us posted.

Dan

ALWAYS to answer your question, refer to the "MIDI IMPLEMENTATION CHART" for your MIDI instrument.

This chart can be found USUALLY near the end of your user's manual.

This chart, among other things, will tell what can be transmitted and received by the MIDI device.

Refering to the chart for your DX21 it shows that the DX21 can both receive and transmit program changes.

If you don't have a user manual, download one here:

http://www.maths.abdn.ac.uk/~bensondj/dx7/manuals/dx21-man.pdf

If you have a board that is bad, repair the board as piece parts of older synths are hard to find. The question is what is wrong with the board? If it is the pressure sensitive part and is not cracked it MIGHT be repairable.

Try powering up the synth, then press and hold the EDIT, 16, & 32 keys (so you end up with all three buttons pressed). I think this will reset it.

Check this link out....lots of helpful info re: v50. Sam

http://www.yamahaforums.co.uk/modules.php?name=Forums&file=viewtopic&t=2460