Stereo receiver, vintage 1973, with uPC554C (ECG1142) FM demodulator chip.
Sounds fine, but the stereo indicator lamp (newly replaced) is on nearly all
the time, when any FM signal is tuned in (even a very weak one), but never
at full brightness. That is not how I remember it behaving, years and years
ago.

Specified bulb is 8 V 40 mA; actual bulb is 8 V 35 mA.

There is no potentiometer to adjust anything to do with the stereo indicator
lamp.

Any thoughts? I plan to replace all the electrolytic capacitors in the
system, a few of which are around the uPC554C. Perhaps one of them is
leaky.

mc wrote:
Stereo receiver, vintage 1973, with uPC554C (ECG1142) FM demodulator chip.
Sounds fine, but the stereo indicator lamp (newly replaced) is on nearly all
the time, when any FM signal is tuned in (even a very weak one), but never
at full brightness. That is not how I remember it behaving, years and years
ago.

Specified bulb is 8 V 40 mA; actual bulb is 8 V 35 mA.

There is no potentiometer to adjust anything to do with the stereo indicator
lamp.

Any thoughts? I plan to replace all the electrolytic capacitors in the
system, a few of which are around the uPC554C. Perhaps one of them is
leaky.

I have a thought. Who needs FM anymore? I takes it it has RCA inputs,
so if I were you, I would get a Sirius Satellite Receiver listen to
that.

Erich J. Schultheis, The Man with the 15 inch Cock. wrote:

mc wrote:

Stereo receiver, vintage 1973, with uPC554C (ECG1142) FM demodulator chip.
Sounds fine, but the stereo indicator lamp (newly replaced) is on nearly all
the time, when any FM signal is tuned in (even a very weak one), but never
at full brightness. That is not how I remember it behaving, years and years
ago.

Specified bulb is 8 V 40 mA; actual bulb is 8 V 35 mA.

There is no potentiometer to adjust anything to do with the stereo indicator
lamp.

Any thoughts? I plan to replace all the electrolytic capacitors in the
system, a few of which are around the uPC554C. Perhaps one of them is
leaky.


I have a thought. Who needs FM anymore? I takes it it has RCA inputs,
so if I were you, I would get a Sirius Satellite Receiver listen to
that.

Why would he want to pay for something he can get for free?

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

"CJT" wrote in message
...
Erich J. Schultheis, The Man with the 15 inch Cock. wrote:

mc wrote:

Stereo receiver, vintage 1973, with uPC554C (ECG1142) FM demodulator
chip.
Sounds fine, but the stereo indicator lamp (newly replaced) is on nearly
all
the time, when any FM signal is tuned in (even a very weak one), but
never
at full brightness. That is not how I remember it behaving, years and
years
ago.

Specified bulb is 8 V 40 mA; actual bulb is 8 V 35 mA.

There is no potentiometer to adjust anything to do with the stereo
indicator
lamp.

Any thoughts? I plan to replace all the electrolytic capacitors in the
system, a few of which are around the uPC554C. Perhaps one of them is
leaky.


I have a thought. Who needs FM anymore? I takes it it has RCA inputs,
so if I were you, I would get a Sirius Satellite Receiver listen to
that.

Why would he want to pay for something he can get for free?


FM is still a very viable medium for entertainment... just because one
person might think it's the cat's meow doesn't mean that it's obsolete.
The adjustment, if any, would be for the pilot level, pilot frequency, or
something similar. I couldn't find a datasheet for either the uPC554 or the
NTE1142, so it's hard to visualize the circuitry around the IC. If you have
a copy of the schematic for your receiver, scan the FM portion and post it
on alt.binaries.schematics.electronic
Replacing the capacitors may help, especially if the unit has been on the
shelf for many years. It may fix problems than you don't even realize that
you have.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in
the address)

Never take a laxative and a sleeping pill at the same time!!

mc wrote:
Stereo receiver, vintage 1973, with uPC554C (ECG1142) FM demodulator chip.
Sounds fine, but the stereo indicator lamp (newly replaced) is on nearly all
the time, when any FM signal is tuned in (even a very weak one), but never
at full brightness. That is not how I remember it behaving, years and years
ago.

Specified bulb is 8 V 40 mA; actual bulb is 8 V 35 mA.

There is no potentiometer to adjust anything to do with the stereo indicator
lamp.

Any thoughts? I plan to replace all the electrolytic capacitors in the
system, a few of which are around the uPC554C. Perhaps one of them is
leaky.




Is there a transistor to drive the lamp? It's possible it's become
leaky. Your replacement lamp should work just fine so there's some fault
in the receiver. It's remotely possible it was damaged when the original
lamp failed.

Why would he want to pay for something he can get for free?




Come on now, quit feeding the trolls, at this rate I'm gonna end up with
half the people in this group killfiled.

CJT wrote:
Erich J. Schultheis, The Man with the 15 inch Cock. wrote:

mc wrote:

Stereo receiver, vintage 1973, with uPC554C (ECG1142) FM demodulator chip.
Sounds fine, but the stereo indicator lamp (newly replaced) is on nearly all
the time, when any FM signal is tuned in (even a very weak one), but never
at full brightness. That is not how I remember it behaving, years and years
ago.

Specified bulb is 8 V 40 mA; actual bulb is 8 V 35 mA.

There is no potentiometer to adjust anything to do with the stereo indicator
lamp.

Any thoughts? I plan to replace all the electrolytic capacitors in the
system, a few of which are around the uPC554C. Perhaps one of them is
leaky.


I have a thought. Who needs FM anymore? I takes it it has RCA inputs,
so if I were you, I would get a Sirius Satellite Receiver listen to
that.

Why would he want to pay for something he can get for free?

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Because it's all 100 percent commercial free music.

have fun talking to yourself then.

Erich J. Schultheis, The Man with the 15 inch Cock. wrote:
CJT wrote:
Erich J. Schultheis, The Man with the 15 inch Cock. wrote:

mc wrote:

Stereo receiver, vintage 1973, with uPC554C (ECG1142) FM demodulator chip.
Sounds fine, but the stereo indicator lamp (newly replaced) is on nearly all
the time, when any FM signal is tuned in (even a very weak one), but never
at full brightness. That is not how I remember it behaving, years and years
ago.

Specified bulb is 8 V 40 mA; actual bulb is 8 V 35 mA.

There is no potentiometer to adjust anything to do with the stereo indicator
lamp.

Any thoughts? I plan to replace all the electrolytic capacitors in the
system, a few of which are around the uPC554C. Perhaps one of them is
leaky.


I have a thought. Who needs FM anymore? I takes it it has RCA inputs,
so if I were you, I would get a Sirius Satellite Receiver listen to
that.

Why would he want to pay for something he can get for free?

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Because it's all 100 percent commercial free music.

Until they get a substantial listener base.

"DaveM" wrote in message
news
Replacing the capacitors may help, especially if the unit has been on the
shelf for many years. It may fix problems than you don't even realize
that you have.

Thanks. I haven't actually gotten around to doing that, but it's in the
queue.

Is there a transistor to drive the lamp? It's possible it's become leaky.
Your replacement lamp should work just fine so there's some fault in the
receiver. It's remotely possible it was damaged when the original lamp
failed.

The driver transistor is inside the uPC554C.

On Mon, 2 Jan 2006 11:32:47 -0500, "DaveM"
put finger to keyboard and composed:

I couldn't find a datasheet for either the uPC554 or the
NTE1142, ...

Pin # Function
-----------------------
1 19kHz tank
2 19kHz tank
3 Input
4 Stereo switch
5 Mute switch
6 Lamp drive
7 Ground
8 NC
9 Vcc
10 38kHz tank
11 Left channel out
12 Right channel out
13 38kHz tank
14 Filter net

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

Thanks!

"Franc Zabkar" wrote in message
...
On Mon, 2 Jan 2006 11:32:47 -0500, "DaveM"
put finger to keyboard and composed:

I couldn't find a datasheet for either the uPC554 or the
NTE1142, ...

Pin # Function
-----------------------
1 19kHz tank
2 19kHz tank
3 Input
4 Stereo switch
5 Mute switch
6 Lamp drive
7 Ground
8 NC
9 Vcc
10 38kHz tank
11 Left channel out
12 Right channel out
13 38kHz tank
14 Filter net

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.