Need help with old auto audio amp

[Doug Sams]

Hi,

I have an old auto audio amplifier from the early 80's. It's a Hi-Comp
by Audiovox, model HCB-820. I had it on the bench tonight but no joy
getting it to work. There's one wire I cannot ID. Perhaps it's the
culprit.

On one end are the speaker outs (R+, R–, L+, L–), +12V and GND. On the
other end are two RCA low-level inputs, left and right high-level input
wires, a black ground wire (which ohms to the jackets on the RCAs) and
two other wires. These last two - pink and orange - are the question
marks. The pink one is labeled "remote on-off". With the unit powered,
I can hear the speakers pop when +12V is applied to the pink, but no
signal is getting thru. Signal source is pre-outs from old receiver
connected to low level inputs. I ran it all the way up to 300mV with no
audible speaker output.

The orange wire was left unconnected. It has a female connector with a
plastic sheath as if it might be hot. Inside the box, it connects to
the pink wire via an unidentified component. This part is axial leaded
and looks like a white sphere about 1/8" in diameter, maybe a tad
smaller. It appears to be ceramic, and had a dark band on the sphere
next to one lead. I've no idea what it is, but it's not a resistor or
capacitor or active component. Any ideas what the component is?

What might the orange wire be? And what should I connect it to?
Ordinarily, if this were a head unit, I might guess it's a connection
for dash lights or power antenna, but since it's a remote amp, I'm
stumped. Any help you can offer will be sincerely appreciated. And a
schematic or hookup diagram would be nirvana :)

TIA.

Doug

[William Noble]

how about tracing out part of the schematic? maybe the remote power on is
active low, not active high? a quick look at a schematic will tell all

"Doug Sams" > wrote in message
t...
> Hi,
>
> I have an old auto audio amplifier from the early 80's. It's a Hi-Comp by
> Audiovox, model HCB-820. I had it on the bench tonight but no joy getting
> it to work. There's one wire I cannot ID. Perhaps it's the culprit.
>
> On one end are the speaker outs (R+, R–, L+, L–), +12V and GND. On the
> other end are two RCA low-level inputs, left and right high-level input
> wires, a black ground wire (which ohms to the jackets on the RCAs) and two
> other wires. These last two - pink and orange - are the question marks.
> The pink one is labeled "remote on-off". With the unit powered, I can
> hear the speakers pop when +12V is applied to the pink, but no signal is
> getting thru. Signal source is pre-outs from old receiver connected to
> low level inputs. I ran it all the way up to 300mV with no audible
> speaker output.
>
> The orange wire was left unconnected. It has a female connector with a
> plastic sheath as if it might be hot. Inside the box, it connects to the
> pink wire via an unidentified component. This part is axial leaded and
> looks like a white sphere about 1/8" in diameter, maybe a tad smaller. It
> appears to be ceramic, and had a dark band on the sphere next to one lead.
> I've no idea what it is, but it's not a resistor or capacitor or active
> component. Any ideas what the component is?
>
> What might the orange wire be? And what should I connect it to?
> Ordinarily, if this were a head unit, I might guess it's a connection for
> dash lights or power antenna, but since it's a remote amp, I'm stumped.
> Any help you can offer will be sincerely appreciated. And a schematic or
> hookup diagram would be nirvana :)
>
> TIA.
>
> Doug
>
>
>



--
Posted via a free Usenet account from http://www.teranews.com

[Matt Ion]

Doug Sams wrote:
> Hi,
>
> I have an old auto audio amplifier from the early 80's. It's a Hi-Comp
> by Audiovox, model HCB-820. I had it on the bench tonight but no joy
> getting it to work. There's one wire I cannot ID. Perhaps it's the
> culprit.
>
> On one end are the speaker outs (R+, R–, L+, L–), +12V and GND. On the
> other end are two RCA low-level inputs, left and right high-level input
> wires, a black ground wire (which ohms to the jackets on the RCAs) and
> two other wires. These last two - pink and orange - are the question
> marks. The pink one is labeled "remote on-off". With the unit powered,
> I can hear the speakers pop when +12V is applied to the pink, but no
> signal is getting thru. Signal source is pre-outs from old receiver
> connected to low level inputs. I ran it all the way up to 300mV with no
> audible speaker output.
>
> The orange wire was left unconnected. It has a female connector with a
> plastic sheath as if it might be hot. Inside the box, it connects to
> the pink wire via an unidentified component. This part is axial leaded
> and looks like a white sphere about 1/8" in diameter, maybe a tad
> smaller. It appears to be ceramic, and had a dark band on the sphere
> next to one lead. I've no idea what it is, but it's not a resistor or
> capacitor or active component. Any ideas what the component is?
>
> What might the orange wire be? And what should I connect it to?
> Ordinarily, if this were a head unit, I might guess it's a connection
> for dash lights or power antenna, but since it's a remote amp, I'm
> stumped. Any help you can offer will be sincerely appreciated. And a
> schematic or hookup diagram would be nirvana :)

I used to have one of those amps... might even still be sitting in a box
somewhere, non-functioning (and no, I didn't actually pay money for it).

The orange, if memory serves, is a remote "output" that lets you "chain"
the remote signal. Not really necessary in itself, as additional
remotes can just be split off the feed... it may include a time-delay,
for example, for delaying turn-off of a crossover or other device, to
eliminate pop.

When you power up the amp by connecting the pink, throw your meter on
the orange and see if it reads +12V. If so, see if it maybe takes a
couple seconds to lose power again after removing power to the pink.

[Matt Ion]

Doug Sams wrote:
> Hi,
>
> I have an old auto audio amplifier from the early 80's. It's a Hi-Comp
> by Audiovox, model HCB-820. I had it on the bench tonight but no joy
> getting it to work. There's one wire I cannot ID. Perhaps it's the
> culprit.
>
> On one end are the speaker outs (R+, R–, L+, L–), +12V and GND. On the
> other end are two RCA low-level inputs, left and right high-level input
> wires, a black ground wire (which ohms to the jackets on the RCAs) and
> two other wires. These last two - pink and orange - are the question
> marks. The pink one is labeled "remote on-off". With the unit powered,
> I can hear the speakers pop when +12V is applied to the pink, but no
> signal is getting thru. Signal source is pre-outs from old receiver
> connected to low level inputs. I ran it all the way up to 300mV with no
> audible speaker output.
>
> The orange wire was left unconnected. It has a female connector with a
> plastic sheath as if it might be hot. Inside the box, it connects to
> the pink wire via an unidentified component. This part is axial leaded
> and looks like a white sphere about 1/8" in diameter, maybe a tad
> smaller. It appears to be ceramic, and had a dark band on the sphere
> next to one lead. I've no idea what it is, but it's not a resistor or
> capacitor or active component. Any ideas what the component is?
>
> What might the orange wire be? And what should I connect it to?
> Ordinarily, if this were a head unit, I might guess it's a connection
> for dash lights or power antenna, but since it's a remote amp, I'm
> stumped. Any help you can offer will be sincerely appreciated. And a
> schematic or hookup diagram would be nirvana :)

I used to have one of those amps... might even still be sitting in a box
somewhere, non-functioning (and no, I didn't actually pay money for it).

The orange, if memory serves, is a remote "output" that lets you "chain"
the remote signal. Not really necessary in itself, as additional
remotes can just be split off the feed... it may include a time-delay,
for example, for delaying turn-off of a crossover or other device, to
eliminate pop.

When you power up the amp by connecting the pink, throw your meter on
the orange and see if it reads +12V. If so, see if it maybe takes a
couple seconds to lose power again after removing power to the pink.

[nesesu]

On Jun 25, 8:59 pm, Doug Sams > wrote:
> Hi,
>
> I have an old auto audio amplifier from the early 80's. It's a Hi-Comp
> by Audiovox, model HCB-820. I had it on the bench tonight but no joy
> getting it to work. There's one wire I cannot ID. Perhaps it's the
> culprit.
>
> On one end are the speaker outs (R+, R-, L+, L-), +12V and GND. On the
> other end are two RCA low-level inputs, left and right high-level input
> wires, a black ground wire (which ohms to the jackets on the RCAs) and
> two other wires. These last two - pink and orange - are the question
> marks. The pink one is labeled "remote on-off". With the unit powered,
> I can hear the speakers pop when +12V is applied to the pink, but no
> signal is getting thru. Signal source is pre-outs from old receiver
> connected to low level inputs. I ran it all the way up to 300mV with no
> audible speaker output.
>
> The orange wire was left unconnected. It has a female connector with a
> plastic sheath as if it might be hot. Inside the box, it connects to
> the pink wire via an unidentified component. This part is axial leaded
> and looks like a white sphere about 1/8" in diameter, maybe a tad
> smaller. It appears to be ceramic, and had a dark band on the sphere
> next to one lead. I've no idea what it is, but it's not a resistor or
> capacitor or active component. Any ideas what the component is?
>
> What might the orange wire be? And what should I connect it to?
> Ordinarily, if this were a head unit, I might guess it's a connection
> for dash lights or power antenna, but since it's a remote amp, I'm
> stumped. Any help you can offer will be sincerely appreciated. And a
> schematic or hookup diagram would be nirvana :)
>
> TIA.
>
> Doug

That component is a GE version of the 1N4000 series of power diode;
the band is the cathode end.

Neil S.