Calling all Sony D-777 owners: lend me your knowledge (and your multimeters)

Hello forum!

I just got my hands on a unit I've been pursuing for quite a while, but for which I was not willing to pay with a lung. I managed to find a D-777 in fair condition for 69€ (nice!) plus shipping. The unit in question was a little rough around the edges and showed no signs of life. The case is complete albeit it shows a few scratches.

The battery pack I had from another unit. The laser was stuck in place, so I took it apart just to discover a few dust bunnies mixed with 20+ years grease. So, I cleaned everything, put some new grease and now it is working as it should. The motor wobbles quite a bit, and the turntable is partially broken (I've seen the problem with other models such as my D465. Easy yet annoying fix), but those are repairs for another day.

But the biggest issue is that I have no remote, which makes it impossible to turn on the bass boost. Compatible remotes like the RM-DM28EL or RM-DM32EL go for quite a few on Ebay (60€ + shipping). So I am looking for a compatible and cheaper remote, or to modify one and make it work.

I discover a GitHub repo, where the owner dives into the electronics of the Sony MD remotes. An schmatic of the TRS 4 pin connector is shown and explains that the button functions are realized by connecting the remote and Vcc pins with a resistor, and the value of the resistor dictates the function. The pin-out is shown in the attachments.


Now, I do not have a remote to measure the resistance between those two pins when the Bass Boost button is pressed in a remote control, hence my request for help. If any of you have a remote that works with the D-777, all I need is for you to measure the resistance between the remote and Vcc pins of the TRS 4 connector while pushing the bass boost button. Even better, you could measure the resistance values for all main functions. It would be awesome to document that in a Git repository for further reference. With that information, I might be able to modify a cheaper controller (say a RM-CD15) to enable the bass boost functionality, of build a simple harness to activate the bass boost only.

Or if any of you is aware of a cheaper controller that works out of the box and has a bass bosst button, please let me know.

Any help provided is appreciated!