DCC730/951 Remote control

Just so I don’t go crazy chasing a problem that doesn’t exist! Does anyone know for a fact that the remote control for the 951 is the same as the one for the 730? I have a 730 remote and a DD82 remote and both are interchangeable & operate each deck no problem but my 951 will not respond. I tried swapping temporarily out the IR receiver but it still won’t work! TIA

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Hi,
Yes they are 100% compatible. The remotes should work on the 730 and 951. It means that either the sensor is defect, or the electronics on the front panel have a problem.

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Philips used the same codes for all DCC recorders (and re-used those codes for MiniDisc recorders after the demise of DCC). So remote controls for all Philips DCC recorders (and their clones, presumably) are interchangeable.

The 730 and 951 are basically identical on the inside except the DCC951 has the ESI bus hookups. There may be minor differences between the front panel boards so that the microcontroller knows whether it’s in a 730 or 951, but any difference will be so small that it shouldn’t matter to your problem.

It’s probably possible to put an LED with a 220 ohm or 150 ohm series resistor on the signal output of the receiver to check if it’s receiving anything (even if it’s from another remote control).

===Jac

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Thx Dr, I have ruled out the sensor as I temporarily fitted one from a 730. I have 5 volts and ground present and the other two pins I have traced back to pin 1 and pin 17 of the front panel IC 7800, beyond this I don’t know.

We had one with the same problem.
We ended up swapping the front panel electronics from a donor, after it turned out that it was not the sensor.

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Thanks @drdcc , typically I have a spare 730 front panel but no 951 spare and they are very different as you no doubt know. :roll_eyes:

If you want to know for sure it is not the remote it self you can do this simple test: switch on the camera on your phone and point the transmitting side towards the lens. Then press a button. Because a digital camera is infrared sensitive you should see a light emitting from the remote.

Fun fact, I use the remote from the DCC300 on all my DCC players. The originals from the 730 and 951 do not have a standby button. The 300 remote does. And it works on the 730 and 951. Why Philips did implemented that functionality in the recorders but didn’t put it on the dedicated remotes is beyond me…


It should look something like this…

The 951 was intended to be used as part of a 900 series set. Surely if you already have one of those, you would plug the recorder into a switchable outlet on the back of the amplifier, and turn the amplifier off.

I used my 730 with a 1987 Philips stereo system most of the time I owned it, and not only did I have it on a switched outlet, I had the stereo connected to a Marantz timer that would take the power off the system.

I never missed the Standby button on my 730 remote control. And even if it would have had one and if my stereo didn’t have switched outlets, I don’t think I would have used it. Why would you want to switch the recorder off or on without switching the rest of the system off or on?

Nevertheless, I expect the “standby” command to be useful as “Borg Sleep” command when I get a little further with my DCC-i project, to put the main microcontroller to sleep while everything else keeps working…

===Jac

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For instance when I’m done listening to the tape and put on a record. I don’t have a 900 dedicated system. But I see your point though. It is not a big deal, but thanks to your explanation I do understand why the functionality is there but it is not supported by the original remote.
Thanks again for the insight!

The functionality is there because the team who programmed the microcontroller, implemented all the remote control codes that they thought would be necessary.

For one thing, they probably looked at the 2nd generation recorders for inspiration and those (some of those?) even have a standby LED. The 3rd generation recorders are very modular so the deck and the main controller software were probably developed without the engineers having any idea what the end product would look like. Let alone what the remote control would look like. They wanted to sell the DDU2113 deck as an OEM module for third party manufacturers too so they had to put everything in there. Unfortunately that plan apparently got zero traction, because even though we have the “sales folder”, we’ve never seen them outside the 730 and 951 recorders.

And there are signs everywhere that Philips wanted to make the 3g recorders as cheap as possible so that sales would go up. That’s probably also why there are no VU meters, even though the deck sends VU values to the front panel many times per second.

Here’s a short video.

===Jac

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So… if I understand you correctly there might be more functionality in these players without is knowing it…

Seeing those little vu meters is magical. How on earth did you figure THAT out!

Maybe in time, @drdcc rdcc can sell us stand alone vu meters. You can ask @techmoan for advice!!!

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Somewhere in the Philips archives are a couple of binders with information on how to interface the DDU2113. Or they’re in a landfill somewhere, who knows. I don’t expect that we’ll ever get to see them unless we get in contact with an engineer who worked on them and made a copy to take home. That was not easy in those days! There were no things like USB sticks or smartphones with cameras.

We could speculate on what kind of commands are implemented but the command bytes are a bit of a mess. It’s not like 1=play 2=stop, 3=unknown, 4=rewind and 5=fast forward so 3 must be play. There is a bit of a system but not much. If you want, you can look at this file in Github to see how much I know now.

Long story short: I figured out with a Logic Analyzer how the bits were going back and forth via the front panel - main MCU connection, and figured out that the protocol was basically SPI mode 3. Then I connected a SAM C21N microcontroller and wrote a program to do a hexdump of the communication. It was quickly clear that the highest bit of the first byte of each message was inverted every time, and that the messages had a 1-byte checksum at the end. From there on out, it was a matter of playing with the buttons while it was dumping to the serial port. I found out quickly that the deck generated often-repeating messages that contained two numbers in binary form, between 0 and 95. Then it was trivial to write a short function that generates a string of ‘=’ characters based on the number. In the beginning, I disabled the display because it made everything else scroll too fast and it was too distracting. Just recently I added some code to simply not generate a line feed so it doesn’t scroll if all it has to print is a VU meter. I also added code (not in the video yet) to print the time code on the same line.

Maybe… But wouldn’t it be cool if there would be a special device that not only shows the VU meters but can also record and play DCC tapes to/from an SD card? I’m thinking of making a front panel replacement that can do all that. It will take quite some time before that will be done though.

===Jac

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That would be confusingly brilliant!
Thank you Jac, and I will read all you suggested to me, can’t promise that I will understand it all though, but thank you nevertheless!

Ahem… first sell us the VU meters, and than the whole panel! Commercially that is a better idea for the museum.

I never told you this…

I didn’t…

I’m sure

I’d never… :rofl:

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Dear Jac,

The DAT 850 even uses the same RC5 codes.
Discovered that when I ruined some recordings on the R-DAT
when I was recording on the DCC600 :slight_smile:

Regards,
Marout Sluijter-Borms

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I didn’t know the DCC/MD codes were already reused from DAT. Interesting to know!

===Jac

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Wait, what?! Philips and MiniDisc? Did I miss something?!

-Philip.

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I had a Marantz “Slimline” stereo from 1995 or 1996 that had a CD player and MiniDisc recorder in a single device. My DCC730 “saw” the codes from the MiniDisc remote control.

=== Jac

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