just opened mine...
...It's an amazing selection of components & equipment for $20...
My paypal address is stuarteasson@yahoo.com, if you want one let me know I'll be checking in on Radio Shack tomorrow.
Stuart
...It's an amazing selection of components & equipment for $20...
My paypal address is stuarteasson@yahoo.com, if you want one let me know I'll be checking in on Radio Shack tomorrow.
Stuart
sorry...
...but AFAIK the only way to make it cheaper is to put it into one of the 'fixed rate' boxes, in which case the cost is ~$35, and those are US dollars, so the price is basically getting cheaper every day...
I have no idea if this thing can be wedged into one of the flat rate boxes. If it can, you won't get the original packaging, but you'll be ~$10 better off...
Stuart
...but AFAIK the only way to make it cheaper is to put it into one of the 'fixed rate' boxes, in which case the cost is ~$35, and those are US dollars, so the price is basically getting cheaper every day...
I have no idea if this thing can be wedged into one of the flat rate boxes. If it can, you won't get the original packaging, but you'll be ~$10 better off...
Stuart
ok, they still have them...
...so it's time to send money, address etc.
Once again if you want one of these things for $20, plus shipping send money and an address via paypal to stuarteasson@yahoo.com.
I'm going to get one today for damianl, if any one else wants one, speak now, or forever hold your peace...
Stuart
...so it's time to send money, address etc.
Once again if you want one of these things for $20, plus shipping send money and an address via paypal to stuarteasson@yahoo.com.
I'm going to get one today for damianl, if any one else wants one, speak now, or forever hold your peace...
Stuart
It's because they don't know what to do with them. . . Radio Shack
will try to give them away with each purchase of 4 batteries.
Thank-you Stuart for trying to save these units from the great
electronic garbage heap. They are quite nice amps for the price --
with the modifications. If it weren't for the 'wife-factor' I would get
several more.
will try to give them away with each purchase of 4 batteries.
Thank-you Stuart for trying to save these units from the great
electronic garbage heap. They are quite nice amps for the price --
with the modifications. If it weren't for the 'wife-factor' I would get
several more.
In this post. . . .great advice. . .read from first entry. . . some pics too!
Bypassing
Rotating
Rewiring
Replacing
Pulling out
Any number of things. . .I rewired the input, bypassed the power
switch to move the AC away from the preamp board, rotated
the transformer, added a preamp output (noisy but functions).
Some have bypassed the whole preamp board. . .said to make
the amp even more quiet. . .with full range speakers. . .the amp
is nice. . .with a sub and supertweeter. . . then you notice the
problems. . .
If the preamp board is bypassed. . .make sure to add a suitable
input cap to block DC. . . there are some electrolytic caps on the
preamp board. . .
Bypassing
Rotating
Rewiring
Replacing
Pulling out
Any number of things. . .I rewired the input, bypassed the power
switch to move the AC away from the preamp board, rotated
the transformer, added a preamp output (noisy but functions).
Some have bypassed the whole preamp board. . .said to make
the amp even more quiet. . .with full range speakers. . .the amp
is nice. . .with a sub and supertweeter. . . then you notice the
problems. . .
If the preamp board is bypassed. . .make sure to add a suitable
input cap to block DC. . . there are some electrolytic caps on the
preamp board. . .
I just picked up one of these yesterday, but have yet to power it up (no cable).
I plan on building a different enclosure for it with a smaller footprint, but now I need to start the process of finding out how to minimize the components.
I'm quite a newbie at amplifiers, so my guess is that the preamp is the volume/balance/bass/treble board? I am curious as how to actually bypass it completely to replace with a single volume pot/knob.
I'm very green with electronics right now, and not sure how to add the pot (I imagine the leftover wire would be the 7-pin bunch on the bottom of the amp board) nor do I know where to add the caps. I don't have a cable so I can't really play around with it with a multimeter, but does anyone have a schematic?
Also curious if anyone has any idea what the missing components would do? (R3, U1, C5 & 6, CN5) I imagine it would be from a different production application of the amp module.
I plan on building a different enclosure for it with a smaller footprint, but now I need to start the process of finding out how to minimize the components.
I'm quite a newbie at amplifiers, so my guess is that the preamp is the volume/balance/bass/treble board? I am curious as how to actually bypass it completely to replace with a single volume pot/knob.
I'm very green with electronics right now, and not sure how to add the pot (I imagine the leftover wire would be the 7-pin bunch on the bottom of the amp board) nor do I know where to add the caps. I don't have a cable so I can't really play around with it with a multimeter, but does anyone have a schematic?
Also curious if anyone has any idea what the missing components would do? (R3, U1, C5 & 6, CN5) I imagine it would be from a different production application of the amp module.
There is a wire bundle of about 6 or 7 wires going down to the main
board from the preamp board. There are only three connections
on this board that you will use if you dump the preamp section. . .
it is worth dumping. . .
Lin, Rin, GND.
Elliot sound has great ideas on volume controls; so does DIY audio
Study other amplifier designs. . .you will see a trend. . . .
The input cap is to protect the amp from DC current. . . there are
some caps in the input path. . .but might not be large enough to
protect the input. . .this thread has some suggestions on what caps
to use. . .the input caps would be in series with the input. Study
the preamp board. . .it has input caps. . . watch polarity if electrolytic. Some even say dump the electrolytic and replace with
better caps. . . just reuse the parts for now. . .upgrade latter.
input siginal ------> >----cap-----> >----amplifier circuit
Study other amplifier designs. . .you will see a trend. . . .
The missing components are probably for some sort of regulation in
the power supply.. .
Happy times they are coming. . .have fun moding.
board from the preamp board. There are only three connections
on this board that you will use if you dump the preamp section. . .
it is worth dumping. . .
Lin, Rin, GND.
Elliot sound has great ideas on volume controls; so does DIY audio
Study other amplifier designs. . .you will see a trend. . . .
The input cap is to protect the amp from DC current. . . there are
some caps in the input path. . .but might not be large enough to
protect the input. . .this thread has some suggestions on what caps
to use. . .the input caps would be in series with the input. Study
the preamp board. . .it has input caps. . . watch polarity if electrolytic. Some even say dump the electrolytic and replace with
better caps. . . just reuse the parts for now. . .upgrade latter.
input siginal ------> >----cap-----> >----amplifier circuit
Study other amplifier designs. . .you will see a trend. . . .
The missing components are probably for some sort of regulation in
the power supply.. .
Happy times they are coming. . .have fun moding.
So far, I've only removed the receiver board and connected the RCA Input jacks to the preamp outputs.
I opened the case today to try to re-route wires to get rid of the annoying power supply noise.
Though I will probably end up bypassing the preamp altogether, I use the amp to drive audio out of my PC, so I can use the variable levels there.
I noticed today that what I thought was PS noise went away with the case off. While looking around, I touched the face place assembly (which is the home of the pre-amp). The noise came back. So, for now, I'm running the amp with no cover. I imagine this artifact will go away when I bypass the entire pre-amp assembly.
Has anyone else noticed this?
I opened the case today to try to re-route wires to get rid of the annoying power supply noise.
Though I will probably end up bypassing the preamp altogether, I use the amp to drive audio out of my PC, so I can use the variable levels there.
I noticed today that what I thought was PS noise went away with the case off. While looking around, I touched the face place assembly (which is the home of the pre-amp). The noise came back. So, for now, I'm running the amp with no cover. I imagine this artifact will go away when I bypass the entire pre-amp assembly.
Has anyone else noticed this?
After about an hour or so of trying to trace the inputs from the 4-pin to the 7-pin plug on the preamp, I finally got the knobs off to get the fornt plate off, and I realize that the wires were labeled all along. 
Now I think I can finally see how this is going to pan out. If I do use the electrolytic caps on the preamp board for the volume pot, how is the polarity labeled on the board (the shaded and non-shaded halves)?
I was also wondering how hot the heatsink gets during extended use? I was thinking about restructuring them (or at least the aluminum support sheet).
Now I think I can finally see how this is going to pan out. If I do use the electrolytic caps on the preamp board for the volume pot, how is the polarity labeled on the board (the shaded and non-shaded halves)?
I was also wondering how hot the heatsink gets during extended use? I was thinking about restructuring them (or at least the aluminum support sheet).
If you traced the input at the preamp board. . .the caps have a
stripe on the negative side. . .use the same polarity. . .as the preamp
board. . .I don't have mine open right now. . . if you use a non-polarity
type cap then you don't have to worry.
I ran my unit into 8ohm power resistors with pink noise at about
3 Vrms overnight. . .they got hot. . . uncomfortable to the touch. . . under
more musical times. . .at loud levels. . .warm as expected. . .those
little output devices would probably die if this amp was used in
extreme conditions for extended periods of time. . . not sure if
too many mods are worth the gain. . . but the front end is where
the work is best placed.
stripe on the negative side. . .use the same polarity. . .as the preamp
board. . .I don't have mine open right now. . . if you use a non-polarity
type cap then you don't have to worry.
I ran my unit into 8ohm power resistors with pink noise at about
3 Vrms overnight. . .they got hot. . . uncomfortable to the touch. . . under
more musical times. . .at loud levels. . .warm as expected. . .those
little output devices would probably die if this amp was used in
extreme conditions for extended periods of time. . . not sure if
too many mods are worth the gain. . . but the front end is where
the work is best placed.
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