How do I "short" the pins?

cjacek

cjacek

Analogue Enthusiast
This is way over my head but I'm sure as easy as pie for many of you... Can you please take a look at the attached? I want to disable dbx for track 1 and 2 (for my Tascam 244) but need to "short" the pins for channels 1 and 2 (at least that's how I understand from the service section). I took the actual plugs out but need to know WHICH PINS TO SHORT AND EXACTLY HOW AND WITH WHAT. I'm completely clueless and need to be lead by the hand. :o Thanks!..... ;)

244.jpg
 
I'm not sure myself Daniel,:confused: but I'm bumpin' your thread back to the top.
I'd be willin' to bet Cory can help you out with this one.
 
You can use buss wire or better yet very thin shielded solid wire. You can also use small paper clips if you’re sure you can keep them from touching.

Since the dbx circuit is taken out of the system what you’re doing by “Shorting” the pins is completing the circuit without the dbx.

Think of it like the send/receive jacks and pins on the back of the 244. The way those are designed there must be a pin in place to complete the signal path (circuit). So basically what you’re doing here is taking a processor out of a send/receive point, and thus you need to complete the circuit minus the dbx processor.

There two sets of pins for each dbx channel and each plastic connector handles two dbx channels. J203 is for channels 1 & 2 and J204 is for channels 3 & 4. The pictures of J203 and J204 show how to connect a piece of wire from one point to the other. 4 wires are needed for the 8 points on each.

You only check one channel at a time so you don’t need to try to jumper everything at once. Start with channel 1.

For channel 1, which is located on J203, connect a wire between pin-jacks 1 & 3, and another wire between pin-jacks 2 & 4.

Now you should see in the instructions the pin-jacks that must be connected for the other channels.

Make sense yet? :)
 
cjacek said:
Thanks my friend, I second that bet. :D ............... ;)
Click to expand...

So...does this mean you BOTH win the bet?

:D

First of all, if you just want to do channels 1&2 you can plug P204 back into the dbx PCB assembly. Less loose stuff hanging out.

Overview: all we're doing is taking the dbx guts out of the loop. P203 brings channels 1&2 into the dbx guts and out. That's why there are 8 pins (+ and ground for 2 channels in and out makes 2 x 2 x 2 = 8). When you unplug P203 you break the connection of the audio and that's why you have to "short" or "jumper" the send and receive sockets on the connector. They want you to pull P205 (the power to the dbx guts) for safety. Just note that with no power to the dbx guts and P204 still plugged into the dbx guts I don't believe channels 3&4 will pass audio while the dbx guts are unpowered. No damage there, just want you to be aware. Anyway, so you just need to jumper the appropriate sockets on P203 with something conductive, some wire.

  1. Those connectors *should* have a numeral 1 located at the edge of the connector that corresponds to socket #1, and the PCB will likely also have a "1" associated with pin 1. The sockets/pins just go in numerical order from there (1, 2, 3,...8). That will get you oriented to pin 1.
  2. Now you need to make some short jumper wires to "short" the sockets according to the instructions. You can use any wire that will fit in the little sockets on J203. There's no need to make the wires really short or anything, you can make them as long as need be so they are easy for you to manipulate. Just strip the ends of the wire so you can stuff them in the sockets of the connector. If you can't find any wire that will work you can also just use something like paper clips but you'll need to wrap some tape around the exposed sections of the paper clip to avoid the signal shorting. BTW, don't worry about blowing anything up...if something WE'RE to short the result would just be a nasty hum.
  3. Once your jumper wires are fabricated simply insert them according to the diagram in the manual (jumper #1 to #3 and #2 to #4 for channel 1, and jumper #5 to #7 and #6 to #8 for channel 2).
  4. Mix and serve.
Does that help?

Lemme go see what guage wire fits in those sockets well...
 
Actually forget stranded wire. I forgot...kind of a challenge to stuff in there unless you solder the stripped wire ends first, and if you do that then probably 20-22awg wire will work best. 18awg even will probably fit.

OR...

If you have any solid core speaker wire...I have a roll of 24awg zip cord that works perfectly.

OR...

Have any scraps of telephone wire or CAT5 cable sitting around? Those small gauge solid-core wires make great jumpers...

ORRRRRRRR...

Just do the paper clip thing...I think if you stagger the clips (bend 1/3 up, 2/4 down, etc.) you don't need to worry about insulating them...should be able to bend/position the paper clips so they don't touch each other.

Small paper clips would work great.
 
Beck said:
No, they both lost! If they'd have said either Beck or Cory... but... and by the way where's my money? (And how much was the bet for?) :p :D
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:laughings:
Sorry Brother Beck,..I just spent it all on a 388!:D
Though,..That was some some good info you & Cory posted!
I wish I had the memory / brain to retain all the knowledge you guys have.
I partied a bit much when I was younger, and now it has taken it's toll!:eek:

Excellent post fellas. Always learning.
 
Beck said:
No, they both lost! If they'd have said either Beck or Cory... but... and by the way where's my money? (And how much was the bet for?) :p :D
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That...is...hilarious...! :D

I saw your post just now and realized you got in before I did...and then I was reading your post and actually had to stop to check and see because for a moment I wasn't sure if I was reading your post or my post!

Daniel's going to get a kick out of this...
 
sweetbeats said:
That...is...hilarious...! :D

I saw your post just now and realized you got in before I did...and then I was reading your post and actually had to stop to check and see because for a moment I wasn't sure if I was reading your post or my post!

Daniel's going to get a kick out of this...
Click to expand...

Great minds! And you nailed it my friend even without knowing I had posted. ;) I've done the same thing... writing and not knowing someone has already posted. We were probably writing much of it at the same time. Yep, you and I should work on a machine together some time... it wouldn't have a chance! :D
 
VESSEL2020 said:
:laughings:
Sorry Brother Beck,..I just spent it all on a 388!:D
Though,..That was some some good info you & Cory posted!
I wish I had the memory / brain to retain all the knowledge you guys have.
I partied a bit much when I was younger, and now it has taken it's toll!:eek:

Excellent post fellas. Always learning.
Click to expand...

I'll take the 388 then. :) :p
 
Tim, Cory ... Great minds indeed! Thanks so much for the thorough explanation, for taking the time. I really, really, really appreciate it. :)
 
sweetbeats said:
Will it get you through, Daniel?
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Cory, of course, thank you very much! Now with all the tools that I have, I'll be damned if I can't find a paper clip!:eek: ... :o Yeah, those paper clips would be perfect indeed. Will work on it later, when the weather cools off a bit. :)

BTW, for inquiring minds, this is not for testing/aligning but for the option of recording without dbx. ;)
 
cjacek said:
BTW, for inquiring minds, this is not for testing/aligning but for the option of recording without dbx. ;)
Click to expand...

Ah, that's a different story. You could wire in min-toggle switches for each channel. The reason I knew where you were and what you were doing right away is because back in the '80s I wired a switch to only channel 4 dbx of my 244 so I could disable it to stripe that track with sync code. Sync and dbx don’t play very nice together. I later upgraded to the 246, which already has switches... one for channel 4 only and one for all channels.

It’s handy if you want to play tapes that weren’t recorded with dbx, but for recording on cassette with such narrow tracks IMO you really need dbx or Dolby C. I prefer dbx because of the expanded headroom and greatly improved crosstalk, not to mention the S/N ratio of course, which is as pin-drop quiet as digital on that unit. Trust me, it’s going to sound like Niagara Falls without dbx. Have fun though experimenting. :)
 
Yeah, have fun, Daniel. I know EXACTLY what you are doing now...how to make a simple unit even more simple...how to track to the 244 with the most direct and true result.

Look forward to any impressions/findings.
 
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