One for the teccies...
 

Fixed a duff tuner for a pal - failed voltage regulator. After fixing,
plugged it into my test amp in the workshop it sounded very lacking in
top. For other reasons I tried it into my main system and it was fine.
Back to the test amp - no top. The test amp is normally fed off a fairly
low impedance pre-amp and isn't DC coupled, and did and does sound fine
off that.

The tuner output is an non inverting op-amp at unity gain with 10 µF in
series with the output with 100k and 0.001µF across that so I'd think
pretty bomb proof. Both channels the same result.

Returned it to the owner who reports it's working fine.

Any clues as to what's going on?

--
*Wrinkled was not one of the things I wanted to be when I grew up

Dave Plowman London SW
To e-mail, change noise into sound.

One for the teccies...
 

"Dave Plowman (News)" wrote in message
...
Fixed a duff tuner for a pal - failed voltage regulator. After fixing,
plugged it into my test amp in the workshop it sounded very lacking in
top. For other reasons I tried it into my main system and it was fine.
Back to the test amp - no top. The test amp is normally fed off a fairly
low impedance pre-amp and isn't DC coupled, and did and does sound fine
off that.

The tuner output is an non inverting op-amp at unity gain with 10 µF in
series with the output with 100k and 0.001µF across that so I'd think
pretty bomb proof. Both channels the same result.

Returned it to the owner who reports it's working fine.

Any clues as to what's going on?

**Test amp is connected to speakers with buggered tweeters.


--
Trevor Wilson
www.rageaudio.com.au



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

One for the teccies...
 

"Dave Plowman (News)" wrote in message
...
Fixed a duff tuner for a pal - failed voltage regulator. After fixing,
plugged it into my test amp in the workshop it sounded very lacking in
top. For other reasons I tried it into my main system and it was fine.
Back to the test amp - no top. The test amp is normally fed off a fairly
low impedance pre-amp and isn't DC coupled, and did and does sound fine
off that.

The tuner output is an non inverting op-amp at unity gain with 10 µF in
series with the output with 100k and 0.001µF across that so I'd think
pretty bomb proof. Both channels the same result.

Returned it to the owner who reports it's working fine.

Any clues as to what's going on?



No idea - it's a mystery to me. Here's another one from *yesterday* -
switching the tuner on (with no aerial attached) as in this pic:

http://www.apah69.dsl.pipex.com/show/leaklenco02.JPG

*Silenced* the little radio which was already on (and which can be seen on
the floor, under the little telly) - on and off repeatedly, like throwing a
switch..!!

??




--
*Wrinkled was not one of the things I wanted to be when I grew up

Dave Plowman London SW
To e-mail, change noise into sound.

One for the teccies...
 

Keith G wrote:
"Dave Plowman (News)" wrote in message
...
Fixed a duff tuner for a pal - failed voltage regulator. After fixing,
plugged it into my test amp in the workshop it sounded very lacking in
top. For other reasons I tried it into my main system and it was fine.
Back to the test amp - no top. The test amp is normally fed off a fairly
low impedance pre-amp and isn't DC coupled, and did and does sound fine
off that.

The tuner output is an non inverting op-amp at unity gain with 10 µF in
series with the output with 100k and 0.001µF across that so I'd think
pretty bomb proof. Both channels the same result.

Returned it to the owner who reports it's working fine.

Any clues as to what's going on?



No idea - it's a mystery to me. Here's another one from *yesterday* -
switching the tuner on (with no aerial attached) as in this pic:

http://www.apah69.dsl.pipex.com/show/leaklenco02.JPG

*Silenced* the little radio which was already on (and which can be seen on
the floor, under the little telly) - on and off repeatedly, like throwing a
switch..!!

??



--
*Wrinkled was not one of the things I wanted to be when I grew up

Dave Plowman London SW
To e-mail, change noise into sound.


Seems like the tuner is radiating like mad. What frequency was the floor
radio tuned to? Did the floor radio go on and off repeatedly by itself,
or did it follow whether the Leak was on and off?

I'd not use the Leak tuner until you find out what's happening. If you
connect it to your main antenna and it *is* radiating, it's possible you
could affect reception of anyone in front of your antenna for quite a
distance.

S.

One for the teccies...
 

"Serge Auckland" wrote in message
...
Keith G wrote:


No idea - it's a mystery to me. Here's another one from *yesterday* -
switching the tuner on (with no aerial attached) as in this pic:

http://www.apah69.dsl.pipex.com/show/leaklenco02.JPG

*Silenced* the little radio which was already on (and which can be seen
on the floor, under the little telly) - on and off repeatedly, like
throwing a switch..!!


Seems like the tuner is radiating like mad. What frequency was the floor
radio tuned to?


Classic FM


Did the floor radio go on and off repeatedly by itself,
or did it follow whether the Leak was on and off?


Followed the Leak exactly. The only thing that was shared was the double
wall socket (tuner took its power from the amplifier). I briefly tried a
ribbon aerial on the Leak tuner and I believe it was exactly the same - it
was only a quick go and I was busy!



I'd not use the Leak tuner until you find out what's happening. If you
connect it to your main antenna and it *is* radiating, it's possible you
could affect reception of anyone in front of your antenna for quite a
distance.


Yes, I immediately thought that it must be some sort of intereference and
thought no more of it.

I don't intend doing anything with the Leak setup - it'll probably be in my
mate Pat's hands (FOC - wot else?) by close of play today!!

No more 'wobbly old ladies' for me - I can't afford to keep giving 'dead
audiophiles' dodgy old 70s kit an expensive 'Viking funeral'...!!

:-)

One for the teccies...
 

I've had opamps go into large oscilations when connecting long co-ax leads
to their outputs, that would cover your loss of treble and the radio prob.
Usual solution is a 10r in series with the opamp output.

Pete

One for the teccies...
 

In article , Keith G
wrote:




Followed the Leak exactly. The only thing that was shared was the double
wall socket (tuner took its power from the amplifier). I briefly tried
a ribbon aerial on the Leak tuner and I believe it was exactly the same
- it was only a quick go and I was busy!



I'd not use the Leak tuner until you find out what's happening. If you
connect it to your main antenna and it *is* radiating, it's possible
you could affect reception of anyone in front of your antenna for
quite a distance.


Yes, I immediately thought that it must be some sort of intereference
and thought no more of it.


Not looked at your pic to check. However if the 'Leak' is something like a
Troughline, the one I have leaks IF and its harmonics, and various mixer
products like a sieve! It appears all over the mains and output cabling.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

One for the teccies...
 

In article ,
Trevor Wilson wrote:

"Dave Plowman (News)" wrote in message
...
Fixed a duff tuner for a pal - failed voltage regulator. After fixing,
plugged it into my test amp in the workshop it sounded very lacking in
top. For other reasons I tried it into my main system and it was fine.
Back to the test amp - no top. The test amp is normally fed off a fairly
low impedance pre-amp and isn't DC coupled, and did and does sound fine
off that.

The tuner output is an non inverting op-amp at unity gain with 10 µF in
series with the output with 100k and 0.001µF across that so I'd think
pretty bomb proof. Both channels the same result.

Returned it to the owner who reports it's working fine.

Any clues as to what's going on?

**Test amp is connected to speakers with buggered tweeters.

Well, they would remain buggered when plugged up again as normal to the
workshop pre-amp, but no, they're fine.

--
*Oh, what a tangled website we weave when first we practice *

Dave Plowman London SW
To e-mail, change noise into sound.

One for the teccies...
 

In article ,
Pete Cross wrote:
I've had opamps go into large oscilations when connecting long co-ax
leads to their outputs, that would cover your loss of treble and the
radio prob.

These were about 12 inches long. ;-) They're the patch leads between
preamp out and amp in in the workshop - and just long enough to reach
something carefully positioned on the bench.

Usual solution is a 10r in series with the opamp output.

Yes - I normally use something approaching that.

--
*I'd kill for a Nobel Peace Prize *

Dave Plowman London SW
To e-mail, change noise into sound.

One for the teccies...
 

Fixed a duff tuner for a pal - failed voltage regulator.

The Tuner is a winter migrant to these shores, and may be finding
difficulty with its habitat. Global warming is known to have unsettled
this particular species and buggered up its internal regulation
system.

The tuner output is an non inverting op-amp at unity gain with 10 ?F
in series with the output with 100k and 0.001?F across that so I'd
think
pretty bomb proof.

The call of the Tuner is as you describe, with a slight trailing off
to the "oooweeee" sound.

Both channels the same result.

Research has shown that estuary habitats are fundamentally similar in
the effects we are witnessing on these birds.


Returned it to the owner who reports it's working fine.

Would this by any chance be a "homing" Tuner? Much rarer than the
ringneck tuner in these parts, but not impossible to spot.


Any clues as to what's going on?

The Tuner (homing or ringneck) is missing the Steppes - pining for
them in fact. It usually rests with its feet nailed to its perch and
clearly has been unsettled by climate change. There is no cure, and
the situation will only get worse.