You might have just heated up the zobel on the output. And yes, all the input ground do have to be tied together. If you managed to get it to work with all the inputs tied together too, good for you. I tried this and got some pretty nasty results.
BTW, if you kill any of the 3 tripath IC's you wont be able to use any of the channels. The dead IC will keep the whole board muted.
Good luck and be careful.
BTW, if you kill any of the 3 tripath IC's you wont be able to use any of the channels. The dead IC will keep the whole board muted.
Good luck and be careful.
Just scored one of these...
I tested it for awhile and then gutted it. I'll soon be putting the information in this forum to good use!
I assume it doesn't matter which mains lead connects to which transformer lead (blue/black).
The remaining parts are up for grabs if anyone needs anything.
I tested it for awhile and then gutted it. I'll soon be putting the information in this forum to good use!
I assume it doesn't matter which mains lead connects to which transformer lead (blue/black).
The remaining parts are up for grabs if anyone needs anything.
Availability Motorola DCP501
Just recently revisited this thread. See that a few others have discovered some of the interesting things about this Audio Receiver! Just for grins, did a search on e-bay for dsp501 and found out that 'grimes8706' is still selling these things. He must have a warehouse full of them! Going price is $69 + $33shipping. Same as the $99 w/free shipping.
I have two of these with only one in use at this time. I want to upgrade the big screen system in the family room. The one in use is downstairs in my 'guy' area. The DSP501 may not be the absolute in High Quality sound, but it sure does a good job of trying. My grandson and I really enjoy the surround sound watching Sci-Fi movies on projection 70inch screen. (Big StarGate fans).
Anyone wanting a halfway decent system for low dollars can't go wrong with these.
Just wanted to add my two cents worth. 🙂
Just recently revisited this thread. See that a few others have discovered some of the interesting things about this Audio Receiver! Just for grins, did a search on e-bay for dsp501 and found out that 'grimes8706' is still selling these things. He must have a warehouse full of them! Going price is $69 + $33shipping. Same as the $99 w/free shipping.
I have two of these with only one in use at this time. I want to upgrade the big screen system in the family room. The one in use is downstairs in my 'guy' area. The DSP501 may not be the absolute in High Quality sound, but it sure does a good job of trying. My grandson and I really enjoy the surround sound watching Sci-Fi movies on projection 70inch screen. (Big StarGate fans).
Anyone wanting a halfway decent system for low dollars can't go wrong with these.
Just wanted to add my two cents worth. 🙂
Member
Joined 2003
Yes, I know...old thread.
I'm finally finishing work on my DCP-501 amp (if you can even call it that anymore). Here's a list of what I did:
-gutted the amp board, and power supply
-installed amp and PSU in a 2U rack chassis
-increased power supply capacitance
-cut tracks at the output of the relays, and wired the speaker terminals directly to the relays.
-replaced input coupling caps with nice polypropylene ones
-speaker grounds wired directly to the power supply star ground
-applied a small modification to the power supply board. I noticed the star ground was connected to the XF centre tap by a couple of small jumper wires, so I replaced these with a thick 16 guage wire.
I thinks that's it. After some initial testing (make sure it's not going to blow up, or blow up my speakers) I plan to be able to listen to it tonight. I am a bit worried of the proximity of the transformer to the amp board, but that's really the only way I could mount everything in this chassis. I'll see how things turn out. Also I'll need to check the heatsink temp that it doesn't get too high or else I'll have to install a fan on the right hand side of the chassis to assist. Note that the pictures don't show the input ground connections.
I'm finally finishing work on my DCP-501 amp (if you can even call it that anymore). Here's a list of what I did:
-gutted the amp board, and power supply
-installed amp and PSU in a 2U rack chassis
-increased power supply capacitance
-cut tracks at the output of the relays, and wired the speaker terminals directly to the relays.
-replaced input coupling caps with nice polypropylene ones
-speaker grounds wired directly to the power supply star ground
-applied a small modification to the power supply board. I noticed the star ground was connected to the XF centre tap by a couple of small jumper wires, so I replaced these with a thick 16 guage wire.
I thinks that's it. After some initial testing (make sure it's not going to blow up, or blow up my speakers) I plan to be able to listen to it tonight. I am a bit worried of the proximity of the transformer to the amp board, but that's really the only way I could mount everything in this chassis. I'll see how things turn out. Also I'll need to check the heatsink temp that it doesn't get too high or else I'll have to install a fan on the right hand side of the chassis to assist. Note that the pictures don't show the input ground connections.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Very Nice mate!
Wonder how it sounds getting the lovey treatment. I'm loving having a 'real' amp again. What a great buy this thing was.
Wonder how it sounds getting the lovey treatment. I'm loving having a 'real' amp again. What a great buy this thing was.
Member
Joined 2003
Well, I powered it on last night, but didn't have any time to look at it. The 5V and 24V lines are low, less than half of what they need to be. The amp rails are good though. Also, it seems that from reading back through this thread, I need to apply 5V to the SPEAK-ON, PROTECT, and P-MUTE pins as well.
Hopefully this issue is only minor and I can repair it tonight.
Hopefully this issue is only minor and I can repair it tonight.
As I mentioned before in the other Truepath post, the speaker ground/signal input ground/power supply grounds need to be connected, and the 5v also need to be connected to the PS board for the amp module to wake.
It took me a while to figure it out, but is well documented on this thread by anonymous1.
Funny, I saw someone on ebay selling their DCP-501 5 channel amp board, toroid and PS board because they could not get it to wake out of standby. I thought about bidding, and also about referring the individual to this thread. I never got around to doing anything, and everything sold for $50.
It took me a while to figure it out, but is well documented on this thread by anonymous1.
Funny, I saw someone on ebay selling their DCP-501 5 channel amp board, toroid and PS board because they could not get it to wake out of standby. I thought about bidding, and also about referring the individual to this thread. I never got around to doing anything, and everything sold for $50.
That be me!
It was this thread that had lead me to buy the DCP-501 and try the amp.
However, once I extricated the amp and wired it up as described in this thread I didn't get any sound. I have a ton of more pressing projects to work on so I sold it off. I sold the other boards awhile back and broke even on the deal.
It was this thread that had lead me to buy the DCP-501 and try the amp.
However, once I extricated the amp and wired it up as described in this thread I didn't get any sound. I have a ton of more pressing projects to work on so I sold it off. I sold the other boards awhile back and broke even on the deal.
I don't feel so bad now. Unless something was tripped up on removing the guts, it should have worked. I have stripped two amps from their chassis and got them both to sing.
The one tricky part was to connect all the signal grounds to all the output grounds to the ground plane on the front end of the power supply. I noticed the ground plane on the back of the power supply was not the same as the front of the power supply.
And connecting the 5v of course.
The one tricky part was to connect all the signal grounds to all the output grounds to the ground plane on the front end of the power supply. I noticed the ground plane on the back of the power supply was not the same as the front of the power supply.
And connecting the 5v of course.
Nice work Dcibel. It looks exactly how I imagined mine were going to look before the "accidents". Just proceed with caution and double check your grounding; it doesn't take much to kill these. You might have better luck since yours is in a metal chassis where it's easier to setup proper grounding. Mine died spread out on the living room carpet.😱
I don't consider the death of my DCPs a total loss. I have used almost every part of both the boards in other projects. I have one of the transformers powering a RB-TA3020 and the other powering a RB-TK2350.
I don't consider the death of my DCPs a total loss. I have used almost every part of both the boards in other projects. I have one of the transformers powering a RB-TA3020 and the other powering a RB-TK2350.
Member
Joined 2003
Living room carpet is a bad place for any electronics...soo much ESD.
Thanks. Unfortunately I didn't get much of a chance to look at the amp last night, but I did manage to get the 5V and 24V up. I had to rip out the ribbon cable for these connections and solder in wires because the ribbon wasn't long enough for the orientation of the boards. Imagine that a single strand of a wire can cause so much trouble.
But...still nothing. I hope that connecting the signal grounds to the power supply star ground will fix it, but that seems like a bit of an odd reason for the amp to not turn on. Power supply works fine though, but once the power is disconnected the rail LED's stay illuminated for a long time, about 10 minutes I'll say, so there's clearly no current draw.
You'd think that a metal chassis would be great for having a good safety earth, but each panel of the chassis has a thick powder coat so I'll have to take it apart somewhat and scrape the powder coat underneath the screws so that I don't have to ground each piece of the chassis separately. It's a Hammond rack chassis if anyone is curious.
Thanks. Unfortunately I didn't get much of a chance to look at the amp last night, but I did manage to get the 5V and 24V up. I had to rip out the ribbon cable for these connections and solder in wires because the ribbon wasn't long enough for the orientation of the boards. Imagine that a single strand of a wire can cause so much trouble.
But...still nothing. I hope that connecting the signal grounds to the power supply star ground will fix it, but that seems like a bit of an odd reason for the amp to not turn on. Power supply works fine though, but once the power is disconnected the rail LED's stay illuminated for a long time, about 10 minutes I'll say, so there's clearly no current draw.
You'd think that a metal chassis would be great for having a good safety earth, but each panel of the chassis has a thick powder coat so I'll have to take it apart somewhat and scrape the powder coat underneath the screws so that I don't have to ground each piece of the chassis separately. It's a Hammond rack chassis if anyone is curious.
OK, I am starting to remember - all signal grounds together and connect to front end groundplane on PS board.
The speaker grounds are ok and do not need to be connected to the input grounds.
The 5v from power supply connects to the three other wires on the input connector block (SPEAK-ON, PROTECT, and P-MUTE pins)
The speaker grounds are ok and do not need to be connected to the input grounds.
The 5v from power supply connects to the three other wires on the input connector block (SPEAK-ON, PROTECT, and P-MUTE pins)
DcibeL said:
Well it was a kind of ESD that killed them I guess...... ESD = Extremely Stupid Decisions.
Member
Joined 2003
Yes, that sounds right, all I am missing at the moment is the input grounds connected to power centre tap on the power supply board. The speaker grounds are connected to the input grounds naturally when this is done.john65b said:
LOL @ theAnonymous1
i have a dismantled dcp501 and a ta3020 ref board. i am intimidated by the necessary steps to maximize the dcp501's potential, also i am only interested in 2 channels. if i apply the dcp's power supply to the ref board could i get max power and fidelity at 4 ohms? is this as simple as it seems if so? i have zero experience in this arena, but am eager to try (fry).i enjoy my AMP7Ts but would rather look at something i made. thank you- anonymous1 and john56b for all the info you have contributed, its been helpful.
Cliftron said:
I have 2 dismantled DCP501's in my stash right now and plan to make 2 amps with them. The first amp will be a 5-channel home theater amp using the boards pretty much as-is with the exception of the input caps which I plan to upgrade to poly films.
The second amp I am going to bridge 2 chips x 2 sets for a 1000Wx2 stereo amp. If you follow the datasheet instructions, it is only a matter of adding a few external components which I can add on the PCB and handwire/cut traces. As for the 5th chip with the single output, I'll prolly either remove the chip itself or cut the power to it to remove the undo current draw on the P/S.
Besides ... you can never have too many 1000W amps laying around!
graigtone, from my reading the ps is not ample enough to drive the multiple bridged 2030 chips to the max . i'm hoping it can do it for 1. if bridging is easily accomplished and could achieve power in the 600 (rather than 1000) watt range per chip w/o shutdown with the stock dcp ps i would be very satisfied. unfortunately the stuff over my head is the 5v connections and disabling the auto shut-down as well as putting higher value caps--basically everything. if someone is interested in posting a dcp mod for dummies i would be your bff and gladly donate to the forum in/on? your behalf. also, if the ps from the dsp would easily work on the ref board that would inevitably leave me with an extra tripath board which i would gladly send to one willing to hold my hand. peace
Remote Conrol for DCP501
Does anyone out there have a remote control for a 501 that they want to part with? I'll gladly pay for it!!
Please contact me at: evan.scores@yahoo.com
Thanks in advance for any help!
catahoulacam
Does anyone out there have a remote control for a 501 that they want to part with? I'll gladly pay for it!!
Please contact me at: evan.scores@yahoo.com
Thanks in advance for any help!
catahoulacam