Yay! It's fixed!
Well, except for the fact that I must now manually switch to enable either internal speakers or headphones. :
Okay, so here's what I did. Once the Pismo was disassembled down to the logic board and DC-In/Sound Board, I extracted the DC-In/Sound board, carefully desoldered the RF shield covering the Line-In and Line-Out jacks. I found that the plastic casing of the 1/8" jack was cracked and unrecoverable. So I desoldered the jack off of the board. I then used the continuity tester built-in on my digital multimeter and a spare unused stereo 1/8" plug, started probing around and taking notes. There are 4 contact points on the jack: 1 for the shield/ground, 1 for the right channel, 1 for the left channel and 1 for the built-in switch to disable the speakers when headphones are plugged in.
When nothing is plugged into the jack, the switch contact and left channel contact are a "closed" circuit. When something is plugged in, the contacts are "open" and the internal speakers are disabled. This culminated into a plan of building an external pigtail jack with in-line switch to manually control where the sound will be fed to. I used a 1 foot section of spare Cat 5e, a spare stereo 1/8" jack and a spare DPDT slide switch I had laying around.
As you all know, Cat 5e has 4 "twisted" pairs of wires inside the cable. I was also concerned about any extra noise (60Hz hum, etc.) that would result from improper Z (impedance) levels. I ended up keeping the pairs together when I went to solder the wires to their proper points on the DC-In/Sound board. The wiring basically was like this:
Orange-White and solid Orange along with Brown-White were soldered together to the left channel pad.
Blue-White and solid Blue were soldered together to the right channel pad.
Green-White and solid Green were soldered together to the shield/ground pad.
Solid Brown was soldered to the switch contact pad.
By keeping the "pairs" soldered together, except Brown, the impedance is dropped in half, because the wires are connected in parallel and twisted together. Three of the pairs are wired this way for the Left, Right and Ground connections. The Brown pair doesn't matter since this is going to be fed to a switch that will open and close to "short" out the left channel, causing the Pismo's DC-In/Sound board to alternate between built-in speakers or the headphone jack.
I ran the wire outside of the Pismo through the remaining headphone out hole in the case and soldered the wires to the proper places on the board. Once that was completed, I reassembled the Pismo and made sure it was booting/working as usual. I then shutdown the computer and got to work soldering together the switch and jack in-line to the Cat 5e cable. Once assembled, I then plugged in a pair of headphones to test and turned on the Pismo. I got OSX booted up and went right into the Sound Control Panel.
I flipped the switch back and forth. Lo and behold, it alternated in the description of feeding sound to Built-in Speakers or Headphones. I then tested volume on both speakers and headphones, reassured it was working properly. I then closed things down and started wrapping electrical tape around the switch, cable and jack. It may look ugly, but more importantly, it just works. I also saved myself some time and money having to buy another replacement board. iFixit.com currently sells the part, but is out of stock at this time. Plus, a replacement would have cost $80 USD plus shipping. I'm strapped for cash and will have to wait until I can afford to permanently replace part for part.
Well, now I can return to things more important, such as editing and producing on this neat laptop.
73s de Phreakout.
Well, except for the fact that I must now manually switch to enable either internal speakers or headphones. :
Okay, so here's what I did. Once the Pismo was disassembled down to the logic board and DC-In/Sound Board, I extracted the DC-In/Sound board, carefully desoldered the RF shield covering the Line-In and Line-Out jacks. I found that the plastic casing of the 1/8" jack was cracked and unrecoverable. So I desoldered the jack off of the board. I then used the continuity tester built-in on my digital multimeter and a spare unused stereo 1/8" plug, started probing around and taking notes. There are 4 contact points on the jack: 1 for the shield/ground, 1 for the right channel, 1 for the left channel and 1 for the built-in switch to disable the speakers when headphones are plugged in.
When nothing is plugged into the jack, the switch contact and left channel contact are a "closed" circuit. When something is plugged in, the contacts are "open" and the internal speakers are disabled. This culminated into a plan of building an external pigtail jack with in-line switch to manually control where the sound will be fed to. I used a 1 foot section of spare Cat 5e, a spare stereo 1/8" jack and a spare DPDT slide switch I had laying around.
As you all know, Cat 5e has 4 "twisted" pairs of wires inside the cable. I was also concerned about any extra noise (60Hz hum, etc.) that would result from improper Z (impedance) levels. I ended up keeping the pairs together when I went to solder the wires to their proper points on the DC-In/Sound board. The wiring basically was like this:
Orange-White and solid Orange along with Brown-White were soldered together to the left channel pad.
Blue-White and solid Blue were soldered together to the right channel pad.
Green-White and solid Green were soldered together to the shield/ground pad.
Solid Brown was soldered to the switch contact pad.
By keeping the "pairs" soldered together, except Brown, the impedance is dropped in half, because the wires are connected in parallel and twisted together. Three of the pairs are wired this way for the Left, Right and Ground connections. The Brown pair doesn't matter since this is going to be fed to a switch that will open and close to "short" out the left channel, causing the Pismo's DC-In/Sound board to alternate between built-in speakers or the headphone jack.
I ran the wire outside of the Pismo through the remaining headphone out hole in the case and soldered the wires to the proper places on the board. Once that was completed, I reassembled the Pismo and made sure it was booting/working as usual. I then shutdown the computer and got to work soldering together the switch and jack in-line to the Cat 5e cable. Once assembled, I then plugged in a pair of headphones to test and turned on the Pismo. I got OSX booted up and went right into the Sound Control Panel.
I flipped the switch back and forth. Lo and behold, it alternated in the description of feeding sound to Built-in Speakers or Headphones. I then tested volume on both speakers and headphones, reassured it was working properly. I then closed things down and started wrapping electrical tape around the switch, cable and jack. It may look ugly, but more importantly, it just works. I also saved myself some time and money having to buy another replacement board. iFixit.com currently sells the part, but is out of stock at this time. Plus, a replacement would have cost $80 USD plus shipping. I'm strapped for cash and will have to wait until I can afford to permanently replace part for part.
Well, now I can return to things more important, such as editing and producing on this neat laptop.
73s de Phreakout.