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Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: pnobles on March 31, 2004, 07:24:50 PM

Title: SBM-1 7 pin / coax mod.
Post by: pnobles on March 31, 2004, 07:24:50 PM
hey all,

i have seen these before, can anyone offer advice on who does them?   is there a guy on the list, known for his sbm mods, who does them ?   please get in touch.

thanks
Pat :afro:
Title: Re:SBM-1 7 pin / coax mod.
Post by: Tim on March 31, 2004, 08:03:09 PM
I'm preparing to sell mine, with coax mod...
Title: Re:SBM-1 7 pin / coax mod.
Post by: pnobles on March 31, 2004, 08:42:10 PM
i just got one, brand new about a week ago...bummer...
Title: Re:SBM-1 7 pin / coax mod.
Post by: nickgregory on March 31, 2004, 08:54:35 PM
I'm preparing to sell mine, with coax mod...

see with that cool coax mod that Todd did, I am almost tempted to buy it and sell mine...
Title: Re:SBM-1 7 pin / coax mod.
Post by: Tim on March 31, 2004, 08:57:36 PM
it's nice. I'm also throwing in a passive 7pin OUT only cable that has one single coax on it...

it's actually at Todd's place right now but I'll pick it up soon.
Title: Re:SBM-1 7 pin / coax mod.
Post by: Lee on April 01, 2004, 01:46:08 AM
Oade will still mod SBMs regardless of where they were bought, FWIW

It actually looks like a simple mod to do if you're good with a soldering iron.  Pretty sure it's the brown wire > tip, brown wire's shield > ring.  I'll take some pictures of mine with the connector apart when I get a chance if you're interested.
Title: Re:SBM-1 7 pin / coax mod.
Post by: wbrisette on April 01, 2004, 06:25:18 AM
Look in the FAQ section. I did the coax mod myself and posted the instructions. I did have the instructions for the cable flipped (probably why the 7 pin never worked once I took it off the SBM-1). Anyhow, the directions are here online and they are pretty simple.

Wayne
Title: Re:SBM-1 7 pin / coax mod.
Post by: Chris K on April 02, 2004, 09:29:05 AM
I'm preparing to sell mine, with coax mod...

see with that cool coax mod that Todd did, I am almost tempted to buy it and sell mine...

Tim....did todd to the mod on that unit, or was it an oade mod, and todd did the coax?

thanks
chris k
Title: Re:SBM-1 7 pin / coax mod.
Post by: Todd R on April 02, 2004, 01:37:05 PM
Oade line-stage mod, I only mod'd it to have a coax output.
Title: Re:SBM-1 7 pin / coax mod.
Post by: nickgregory on April 02, 2004, 01:38:19 PM
how difficult is the coax on the unit mod vs the one where oade just modifies the pigtail?
Title: Re:SBM-1 7 pin / coax mod.
Post by: Chris K on April 02, 2004, 01:49:35 PM
Oade line-stage mod, I only mod'd it to have a coax output.

thanks todd....i still have your modded sbm-1 that i bought a while back. love it, love it!

Title: Re:SBM-1 7 pin / coax mod.
Post by: Todd R on April 02, 2004, 02:15:41 PM
Oade line-stage mod, I only mod'd it to have a coax output.
thanks todd....i still have your modded sbm-1 that i bought a while back. love it, love it!

Cool, Chris, glad to hear you're digging it!
Title: Re:SBM-1 7 pin / coax mod.
Post by: Todd R on April 02, 2004, 02:51:44 PM
how difficult is the coax on the unit mod vs the one where oade just modifies the pigtail?

It really isn't too difficult to do, just tedious, and requires working in very tight quarters.  I put the one in for Tim next to the existing RCA analog input jacks.  There is enough room in there to put in another RCA jack for the coax out, but not very much.

You'll need to get an RCA jack with a nut for securing it to the SBM1 chassis.  (There really will be so little room that using the nut will be difficult--I tried doing it just by screwing the jack into the plastic of the SBM wall, but Simpy proved that wasn't the most robust design.)  You'll have to drill out a hole for the jack in the side of the SBM1.  There will be very little margin for error as to where exactly the jack will need to go, so plan accordingly, including making sure there will be room for the securing nut above the circuit board.  Then disassemble the whole SBM1 to get the circuit guts out of the case, so you can drill a hole into the case to fit the jack (you'll need the right diameter drill bit).  To get it completely apart, you'll need to take off the volume level knobs.  To do this you need to take off the rubber gasket that goes around the knob to help provide grip.  Underneath the rubber gasket is a screw that will release the knob from the post.  You might be able to do the drilling without pulling everything apart, but be very careful the drill bit doesn't rip into the circuit board if you choose to do it this way.

Then you'll need to put guts of the unit back in place.  Unfortunately with this mod, the coax jack will need to be the last thing put into the SBM1 case.  If you need to pull out the circuit board to do any kind of service or modification of the line input stages or whatever, you'll need to pull apart the soldering of the coax jack and remove it.

With everything back in place, there will be very little room to work (have I mentioned this before?  starting to get the picture?).  First, secure the RCA jack into the hole you drilled with the nut.  Now all you have to do is make the solder connections.  You just need to follow previous directions on replacing the 7pin tail with a coax.  The SBM uses two circuit boards sandwiched together, which seemed too difficult to want to pull apart.  Unfortunately, the points on the board where the 7pin tail connects are between these two boards and you can't get at them without pulling everything apart.  So I found it easier to hack down the 7pin tail to just an inch or so, and use the existing wires to make the connections.  Find the brown wire with the ground shield wires in the wire bundle.  The ground shield wires go to the outer ground portion of the RCA jack.  The brown wire gets connected to the inner portion of the RCA jack.  Soldering in these tight quarters will be difficult.  

You will probably need to rotate the jack around to get at the tab for the ground connection, make the solder connection, and then tighten down the RCA jack to rotate the jack around so that the ground tab is down at the 6 o'clock position and the center tab of the RCA jack is now available to get soldered.  You probably won't be able to turn the securing nut to tighten things, so you will need to turn the jack into the nut to secure things, and when it is almost completely tightened, stop turning so that the ground tab is up.  Make that connection and then tighten it the rest of the way so that the ground tab is down.  Then make the final solder connection of the brown wire to the center.  Then you're done.  Well, after you put it all together.  Be sure when doing this that you get the slider switches on the outer case (for 32k-44k-48k and whatever else) aligned with the actual switches on the circuit board.

It really isn't technically difficult, just very tedious due to the small spaces you need to work in, and time consumed to pull everything apart and put it back together.  You also have to have a steady hand for soldering in the tight spaces required.

Good luck!
Title: Re:SBM-1 7 pin / coax mod.
Post by: Tim on April 02, 2004, 03:10:33 PM
jesus todd, I owe you big for doing that for me... thanks again man.
Title: Re:SBM-1 7 pin / coax mod.
Post by: KC5 on April 02, 2004, 03:21:31 PM
is there a pic of the coax mod todd r does?

Title: Re:SBM-1 7 pin / coax mod.
Post by: pnobles on April 02, 2004, 03:24:11 PM
i would like to see a picture if there is one out there.   thanks -
Title: Re:SBM-1 7 pin / coax mod.
Post by: Tim on April 02, 2004, 03:30:02 PM
here ya go...

(http://www.taperssection.com/yabbse/attachments/rig_one_013.jpg)

(http://www.taperssection.com/yabbse/attachments/rig_one_014.jpg)

Title: Re:SBM-1 7 pin / coax mod.
Post by: KC5 on April 02, 2004, 03:51:27 PM
nice job,
looks great.
Title: Re:SBM-1 7 pin / coax mod.
Post by: nickgregory on April 02, 2004, 03:57:08 PM
very nice Todd...may have to get motivated one day and try it...thanks for the description!
Title: Re:SBM-1 7 pin / coax mod.
Post by: Chris K on April 02, 2004, 05:23:12 PM
no way i'm trying that...i'll stick with the 7pin i/o cable from pro-dig....although that side coax sure looks perty

thanks again todd for the great work and write up on this, but my pea brain knows that i would just f*ck it up so i'll leave well enough alone

HEY WAIT

i dont see the pigtail on the back of that sbm-1 tim...am i seeing that right???
Title: Re:SBM-1 7 pin / coax mod.
Post by: Tim on April 02, 2004, 05:29:34 PM
yes, the pigtail was removed for this.

I have a passive 7pin cable that todd modified into an OUT only 7pin, with just an rca barrell that plugs into the 7pin on the back of the sbm
Title: Re:SBM-1 7 pin / coax mod.
Post by: Chris K on April 02, 2004, 05:39:36 PM
yes, the pigtail was removed for this.

I have a passive 7pin cable that todd modified into an OUT only 7pin, with just an rca barrell that plugs into the 7pin on the back of the sbm

so that's 2 outs....where's the in

would be cool if todd put a switch on there next to the chasis mounted coax to switch between and "in" option, and an "out" option....but that may be overkill.

cool but overkill...

wow, i'm almost at 420 posts.... ;D
Title: Re:SBM-1 7 pin / coax mod.
Post by: Tim on April 02, 2004, 05:51:55 PM
in? why would I need a digital input on an sbm-1?
Title: Re:SBM-1 7 pin / coax mod.
Post by: pnobles on April 04, 2004, 01:53:58 PM
thats hot!   i'll try that one day - when i donthave shows coming up ( therefore if i fuck it up - i have alittle time to fix it )
Title: Re: SBM-1 7 pin / coax mod.
Post by: crunchy on August 19, 2004, 11:18:03 AM
Would it be possible to do this coax mod and then have an optical out where the 7 pin cables was? BTW that mod looks sweet.
Title: Re: SBM-1 7 pin / coax mod.
Post by: caymanreview on August 19, 2004, 07:21:19 PM
it is possible, and i believe there are directions and/or part numbers from Doug on the oade board
Title: Re: SBM-1 7 pin / coax mod.
Post by: JAH on August 24, 2004, 02:48:00 PM
Would it be possible to do this coax mod and then have an optical out where the 7 pin cables was? BTW that mod looks sweet.
why not use a 7 pin optical?
jah

btw nice job Todd.
Title: Re: SBM-1 7 pin / coax mod.
Post by: macdaddy on August 30, 2004, 09:30:12 PM
I'm stoopid, but what's the main usage of this mod?  Is it to pass the sbm-1 into a different recorder than a sony dat(jb3, other portable dats)?  i assume that's what it's for but i just want to be sure, satisfy my curiosity.  I suppose i wonder what other benefits this has...thanks and it  looks very nice.
yes, it is to have a digital output other than the sony 7pin...