FM multiplex decoder.

[Patrick Turner]

I have a Leak Troughline tuner here for alignment, which I have done,
and it has a Leak solid state stereo MPX unit fitted within, but from
what
I see on the CRO, it isn't a very good performer, and has a lot of noise
products
in the outputs due to the 19kHz and 38 kHz artifacts, and there is no
filtering for these.

It sounds passable, but could be better.

My client hasn't got the funds to pay me to do a tubed stand alone MPX
unit,
and after a search on Ebay etc, there wasn't much around that is cheap
and worth aquiring.
I was looking for a chip based unit which is at least better than the
Leak original with 3 ancient transistors, AC126, probably germanium.

I once fitted a Studio12 kit into a Kenwood reciever which was very
successful,
but even it had a lot of noise in the outputs, but not as much as the
original Leak.
I have the circuit for the Studio12, but is there anyone else
selling MPX kitsets?

Patrick Turner.

[Sander deWaal]

Post by Patrick Turner
I have the circuit for the Studio12, but is there anyone else
selling MPX kitsets?

See:
http://users.otenet.gr/~athsam/stereo_decoder_3.htm using MC1310P
http://users.otenet.gr/~athsam/stereo_decoder_4.htm using LM1800N

General schematics site ( very useful!) :
http://rlocman.ru/en/out.htm

[Patrick Turner]

Post by Sander deWaal

Post by Patrick Turner
I have the circuit for the Studio12, but is there anyone else
selling MPX kitsets?

http://users.otenet.gr/~athsam/stereo_decoder_3.htm using MC1310P
http://users.otenet.gr/~athsam/stereo_decoder_4.htm using LM1800N

The LM1800 is the basis of the Studio12 circuit shown at
Loading Image...
The one above has buffer opamps to do the de-emphasis,
but still no filters to clean out the 38 kHz switching artifacts.

I may well settle for using one of these chips on a bit of board,
but it means finding all the parts, doing my own board design with
solid wire links, and all that takes time.
A kitset of this size is a 1 hour soldering job.

Patrick Turner.

Post by Sander deWaal
http://rlocman.ru/en/out.htm
--
Sander deWaal
"SOA of a KT88? Sufficient."

[Sander deWaal]

Post by Patrick Turner

Post by Sander deWaal

Post by Patrick Turner
I have the circuit for the Studio12, but is there anyone else
selling MPX kitsets?

http://users.otenet.gr/~athsam/stereo_decoder_3.htm using MC1310P
http://users.otenet.gr/~athsam/stereo_decoder_4.htm using LM1800N

The LM1800 is the basis of the Studio12 circuit shown at
http://werple.net.au/~kiewavly/Leak/stereo_dec3.gif
The one above has buffer opamps to do the de-emphasis,
but still no filters to clean out the 38 kHz switching artifacts.
I may well settle for using one of these chips on a bit of board,
but it means finding all the parts, doing my own board design with
solid wire links, and all that takes time.
A kitset of this size is a 1 hour soldering job.

So is the MC1310P solution IMO. Only a handful of passive parts to add
and there you are. Even Quad used it :-)
You can always add some Toko filters afterwards.

Don't you have some old tuner or receiver sitting on the shelf to
scavenge your parts from?
Or even an old cassettedeck, you can often find LC filters at the rec.
inputs as well.

[Jon Yaeger]

Post by Sander deWaal

Post by Patrick Turner

Post by Sander deWaal

Post by Patrick Turner
I have the circuit for the Studio12, but is there anyone else
selling MPX kitsets?

http://users.otenet.gr/~athsam/stereo_decoder_3.htm using MC1310P
http://users.otenet.gr/~athsam/stereo_decoder_4.htm using LM1800N

The LM1800 is the basis of the Studio12 circuit shown at
http://werple.net.au/~kiewavly/Leak/stereo_dec3.gif
The one above has buffer opamps to do the de-emphasis,
but still no filters to clean out the 38 kHz switching artifacts.
I may well settle for using one of these chips on a bit of board,
but it means finding all the parts, doing my own board design with
solid wire links, and all that takes time.
A kitset of this size is a 1 hour soldering job.

So is the MC1310P solution IMO. Only a handful of passive parts to add
and there you are. Even Quad used it :-)
You can always add some Toko filters afterwards.
Don't you have some old tuner or receiver sitting on the shelf to
scavenge your parts from?
Or even an old cassettedeck, you can often find LC filters at the rec.
inputs as well.

Patrick,

I've got a tube MPX PCB or two that have the filters on them. Would be
happy to ship one to you @ NC.

- Jon

[Patrick Turner]

Post by Jon Yaeger
Patrick,
I've got a tube MPX PCB or two that have the filters on them. Would be
- Jon

Exactly what is on the pcb?
I may well be interested in purchasing something from you.
What's "@ NC" mean?
My customer would be more interested in a tubed decoder.

I did a search for decoder chips from local suppliers,
and I found only two, CA1310, HA1196, but I couldn't find the
application notes and the included typical schematics.
In fact I spent 3 hrs searching the web, and although I found schemos for
LM1800 and LM1870, I couldn't find a local supplier.
If it ain't one thing, its another.

Patrick Turner.

[Steve Bench]

Post by Patrick Turner
I found schemos for
LM1800 and LM1870, I couldn't find a local supplier.
If it ain't one thing, its another.

Hey Patrick,
If you have access to NTE stuff, there's
an NTE crossref to LM1800.

Best Regards,
Steve

[Patrick Turner]

Post by Steve Bench

Post by Patrick Turner
I found schemos for
LM1800 and LM1870, I couldn't find a local supplier.
If it ain't one thing, its another.

Hey Patrick,
If you have access to NTE stuff, there's
an NTE crossref to LM1800.

The apparent equivalant chip to LM1800 is the NTE743.
The data comes up, but no schematic.
I couldn't find a schematic for NTE1217,
and I cannot get a schemo for the two which are available locally,
a CA1310 and HA1196.

There are hundreds of thousands of chips out there......
And only one circuit will work for each one.

Maybe I have to copy the schemo of something from my files of
old SS receiver schemos.

There is only so much unpaid for time I can waste searching.

Patrick Turner.

Post by Steve Bench
Best Regards,
Steve

[Phil Allison]

"Patrick Turner"

Post by Patrick Turner
and I cannot get a schemo for the two which are available locally,
a CA1310 and HA1196.

** The LM1310, CA1310 and HA1196 are electrically the same.

Post by Patrick Turner
There are hundreds of thousands of chips out there......
And only one circuit will work for each one.

** Fucking bullshit.

LM 1310 schematics are available on the net.





........ Phil

[Patrick Turner]

Post by Phil Allison
"Patrick Turner"

Post by Patrick Turner
and I cannot get a schemo for the two which are available locally,
a CA1310 and HA1196.

** The LM1310, CA1310 and HA1196 are electrically the same.

Thanks, nothing I saw indicated that this was the case

Post by Phil Allison

Post by Patrick Turner
There are hundreds of thousands of chips out there......
And only one circuit will work for each one.

** Fucking bullshit.

Well, I didn't know whether the BS you speak of can copulate,
as well as lay around in paddocks.......

Post by Phil Allison
LM 1310 schematics are available on the net.

I have not seen one yet.

I only searched for a few hours......

In fact after searching my paper files, the Quad FM3 tuner is here,
but its from a guy who sent it to me years ago and the the copy is
barely readable.

The one I repaired had a shorted bypass cap on the IF amp.

I suspect the decoder could be an MC1310P,
but all the surrounding R&C values are unreadable, but I can see enough
to suggest that this decoder has good HF filtering and buffereing after
the decoder chip,
because there are emitter followers with RC feedback loops in there.

I think perhaps this would be a better design than the Studio12 listed
at the Leak Kiewa Valley site.

And now you have reminded me, I have found a wireless world circuit from
March, 1976,
which has the MC1310P within it, and fortunately, its quite readable.
There is no post chip filters.

I also have the Leak Troughline tuner decoder add on unit as designed by

Tim de Paravicini, and it has an anode follower input buffer, MC1310
chip decoder,
two opamps, and 3 triodes, which I can't figure right now.
Its not an all tube design, and derives the mono signal after the
decoder chip,
which seems silly, when the L+R is already available from the tuner
before the decoder.

Patrick Turner.

Post by Phil Allison
........ Phil

[Jon Yaeger]

Post by Patrick Turner

Post by Jon Yaeger
Patrick,
I've got a tube MPX PCB or two that have the filters on them. Would be
- Jon

Exactly what is on the pcb?
I may well be interested in purchasing something from you.
My customer would be more interested in a tubed decoder.
I did a search for decoder chips from local suppliers,
and I found only two, CA1310, HA1196, but I couldn't find the
application notes and the included typical schematics.
In fact I spent 3 hrs searching the web, and although I found schemos for
LM1800 and LM1870, I couldn't find a local supplier.
If it ain't one thing, its another.
Patrick Turner.

This is the National semiconductor book I was talking about, describing the
LM1310P: http://www.hificollective.co.uk/b/bk6001c.html. I think . . . but
don't remember for sure . . . since it was probably 20 years since I last
looked at it . . . that they had a PCB layout for it in the handbook.

Here's a link with lots of Ics, including schematics:
http://art-pipes.com/electronics/schematics.htm. The TDA part has complete
application info PLUS a PCB. Xmas in Sept.

NC means "no charge" = free. I have a tubed module measuring about 3-1/2
square that takes two 6CG7s. Came out of a Nipponese receiver, complete
with coils, diodes, etc. and the usual bad Jap grey caps. I think I took it
out of a Pioneer receiver but I don't remember the model #. I clipped the
wires going to it but it is easy to see what is B+, Gnd, Audio Out, and RF
in.

I'll send it with your choice of LM1800 or LM1870, which I believe I can get
from a local supplier, also NC. Hey, you don't charge me for technical
advice . . .

;-)

[Patrick Turner]

Post by Jon Yaeger

Post by Patrick Turner

Post by Jon Yaeger
Patrick,
I've got a tube MPX PCB or two that have the filters on them. Would be
- Jon

Exactly what is on the pcb?
I may well be interested in purchasing something from you.
My customer would be more interested in a tubed decoder.
I did a search for decoder chips from local suppliers,
and I found only two, CA1310, HA1196, but I couldn't find the
application notes and the included typical schematics.
In fact I spent 3 hrs searching the web, and although I found schemos for
LM1800 and LM1870, I couldn't find a local supplier.
If it ain't one thing, its another.
Patrick Turner.

This is the National semiconductor book I was talking about, describing the
LM1310P: http://www.hificollective.co.uk/b/bk6001c.html. I think . . . but
don't remember for sure . . . since it was probably 20 years since I last
looked at it . . . that they had a PCB layout for it in the handbook.
http://art-pipes.com/electronics/schematics.htm. The TDA part has complete
application info PLUS a PCB. Xmas in Sept.
NC means "no charge" = free. I have a tubed module measuring about 3-1/2
square that takes two 6CG7s. Came out of a Nipponese receiver, complete
with coils, diodes, etc. and the usual bad Jap grey caps. I think I took it
out of a Pioneer receiver but I don't remember the model #. I clipped the
wires going to it but it is easy to see what is B+, Gnd, Audio Out, and RF
in.

Well now, that's a step up in my fortunes!
My customer may prefer to pay me an extra $ for the tubed decoder,
and besides, I learn from the experience, and I'll document the work,
and post the results back to you all.
I have to know all about what I make; I am one of the only tube service
ppl here in this town.

I could easily decode what the tubes used in the decoder are trioding to do!!

But one could never work out the circuit used for a chip.

And it allows me to try 6DJ8; they are not bad where 6CG7
were used for signal work.

I designed and built my own decoder seen at
http://www.turneraudio.com.au/htmlwebpgs02/schemampxdecoder.htm

I think I spent a month foolin around until I got that design to work OK,
and also make use of the Trio parts which were in the receiver.
The original Trio made the stereo sound like it was coming down a
drain pipe.
I know I couldn't reproduce that effort unless I had the coils.
This is the problem when doing anything like this.

Post by Jon Yaeger
I'll send it with your choice of LM1800 or LM1870, which I believe I can get
from a local supplier, also NC. Hey, you don't charge me for technical
advice . . .

The LM1800 needs a tunable coil for the 19 kHz, but apparently not
on the LM1800N, which has a pot to tune the 19 kHz
I don't know about the LM1870.
A quality adjust multi turn cermet pot is easier to find than a bloomin coil.



My address is

Patrick Turner,
1 Adams Pl,
Watson,
ACT 2602,
Australia.

Regards,

Patrick Turner.

[Phil Allison]

"Patrick Turner

Post by Patrick Turner
The LM1800 needs a tunable coil for the 19 kHz,

** Complete bullshit.

Post by Patrick Turner
I don't know about the LM1870.

** Also coil free.



.......... Phil

[Patrick Turner]

Post by Phil Allison
"Patrick Turner

Post by Patrick Turner
The LM1800 needs a tunable coil for the 19 kHz,

** Complete bullshit.

The cicuit I have shows a coil. I assumed it was required.
I don't build decoders everyday.

Patrick Turner.

Post by Phil Allison

Post by Patrick Turner
I don't know about the LM1870.

** Also coil free.
.......... Phil

[Phil Allison]

"Patrick Turner"

Post by Patrick Turner

Post by Phil Allison
"Patrick Turner

Post by Patrick Turner
The LM1800 needs a tunable coil for the 19 kHz,

** Complete bullshit.

The cicuit I have shows a coil.

** On what pin ?

Doing what ?


Quote from the Natsemi LM1800 data sheet :


" # No coils, all tuning performed with a single potentiometer."





.......... Phil

[Patrick Turner]

Post by Phil Allison
"Patrick Turner"

Post by Patrick Turner

Post by Phil Allison
"Patrick Turner

Post by Patrick Turner
The LM1800 needs a tunable coil for the 19 kHz,

** Complete bullshit.

The cicuit I have shows a coil.

** On what pin ?
Doing what ?
" # No coils, all tuning performed with a single potentiometer."
.......... Phil

Due to your response to Lyle and your on-going
defamation of my character in your last post here,
I can only decline to further discuss the issue of
of stereo decoders with you.

I don't rely on too many other people for what I know,
and I sure will not rely on your contributions if they are framed with
insults.
I will find out about the LM1800 without your help;
I don't want it.

No doubt that those who had you off their killfile list will place you
back on.



Patrick Turner.

[Phil Allison]

"Patrick Turner"

Post by Patrick Turner
Due to your response to Lyle and your on-going
defamation of my character in your last post here,

** The Turneroid has no character left to defame.

Posting criminal threats here against me was the end of that.

Post by Patrick Turner
I can only decline to further discuss the issue of
of stereo decoders with you.

** What discussion ?????

Correcting more of the Turneroid's dumb errors is not debate.

Post by Patrick Turner
No doubt that those who had you off their killfile list will place you
back on.

** There sure are some low scumbags posting on this NG.




.......... Phil

[Jon Yaeger]

Post by Patrick Turner
No doubt that those who had you off their killfile list will place you
back on.
Patrick Turner.

Frankly, it's hard to imagine why anyone would want to take him back OUT of
their killfile. That is, unless you enjoy the abuse . . . And Patrick, I'm
not so sure you don't . . . .

-J

[Patrick Turner]

Post by Jon Yaeger
Frankly, it's hard to imagine why anyone would want to take him back OUT of
their killfile. That is, unless you enjoy the abuse . . . And Patrick, I'm
not so sure you don't . . . .

Well, frankly he hasn't been too "off his rocker" for the last few months.
Then today, boom, all over some SFA thing.
I don't have a killfile. And I don't enjoy any pita.

Patrick Turner.

[Lyle Harbour]

Hey Phil
In life are you the kinda guy who strives in life to make more
deposits than withdrawals.
Or are you in the rape an pillage category.
Better to be in credit in the world rather than be in debit.
Do you have something constructive to add. All positive and helpfull posts
welcome
Some whom hold Patrick's help in such high regard are willing to post no
charge
components to him to help with what he is trying to acheive.
Full mark's to them an there experiances
Should you decide to contribute positively to the principal of what you send
arround
comes arroud .Your life in this ,or hopefully the next few will improve out
of site
I am certain that what you can contribute, can benifit others as much as
what others
can contribute to you . But hey we are given free will to choose as we may.

Have a great day
Regards
Lyle


Phil please post your possible answers to Patrick's question . The word
bullshit
is of no help to anybody.

Post by Phil Allison
"Patrick Turner

Post by Patrick Turner
The LM1800 needs a tunable coil for the 19 kHz,

** Complete bullshit.

Post by Patrick Turner
I don't know about the LM1870.

** Also coil free.
.......... Phil

[Patrick Turner]

Post by Lyle Harbour
Hey Phil
In life are you the kinda guy who strives in life to make more
deposits than withdrawals.
Or are you in the rape an pillage category.
Better to be in credit in the world rather than be in debit.
Do you have something constructive to add. All positive and helpfull posts
welcome
Some whom hold Patrick's help in such high regard are willing to post no
charge
components to him to help with what he is trying to acheive.
Full mark's to them an there experiances
Should you decide to contribute positively to the principal of what you send
arround
comes arroud .Your life in this ,or hopefully the next few will improve out
of site
I am certain that what you can contribute, can benifit others as much as
what others
can contribute to you . But hey we are given free will to choose as we may.
Have a great day
Regards
Lyle

With all due respect Lyle, its best you ignore some things Phil says.


I am not someone whose ears will fall off if I am called a bullshit artist.
Its happened before, when I was being a bullshit artist.
Nobody is perfect, and despite Phil's occasional
unpolished way of putting things, he is sometimes informative.
When he says "** The LM1310, CA1310 and HA1196 are electrically the same.",
it made things a bit easier for me because I realised I did have some schematics
I could use
to make a decoder.

Its possible Phil may know where to look for info on such chips, and he isn't
telling us,
but that's his right.
He might even know of the best chip to use, but almost anything would be better
than the
existing Leak decoder.

And I use an Audio Reflex tuner for a sound source in the workshop, and it has a

HA1196 chip in there, and it sounds quite reasonable.
(...)

Post by Lyle Harbour

Post by Phil Allison

Post by Patrick Turner
The LM1800 needs a tunable coil for the 19 kHz,

** Complete bullshit.

Post by Patrick Turner
I don't know about the LM1870.

** Also coil free.

The Studio 12 kit has a LM1800 and it used a coil and cap tuned to the 19 kHz
pilot tone. And in the kit instructions and talk on the Studio 12, it was
recomended the coil from the
old Leak decoder be transfered to the board which used the chip, perhaps because

more chip stability could be achieved.
I found that in my own design of decoder, I needed two tuned
LCs to pick out the 19 kHz, and not have spurious audio signals
affect the stability of the locked oscillator.
Phil may be quite right when he says a coil isn't needed, but perhaps one could
be used anyway.

Patrick Turner

[Phil Allison]

"Lyle Harbour"


** Hey Lyle - you are bloody idiot.

Pat Turner is not a nice guy - he is a dangerous crazyman.

He launched into a vile hate campaign here against me and then posted
criminal threats against my life on this NG forcing me to seek legal advice
and put him on strict notice by registered letter that I intended to report
any recurrence to the Federal Police.

Kindly stick you dumb opinions up your fat arse.



............ Phil

[Jon Yaeger]

Post by Patrick Turner

Post by Jon Yaeger

Post by Patrick Turner

Post by Jon Yaeger
Patrick,
I've got a tube MPX PCB or two that have the filters on them. Would be
- Jon

Exactly what is on the pcb?
I may well be interested in purchasing something from you.
My customer would be more interested in a tubed decoder.
I did a search for decoder chips from local suppliers,
and I found only two, CA1310, HA1196, but I couldn't find the
application notes and the included typical schematics.
In fact I spent 3 hrs searching the web, and although I found schemos for
LM1800 and LM1870, I couldn't find a local supplier.
If it ain't one thing, its another.
Patrick Turner.

This is the National semiconductor book I was talking about, describing the
LM1310P: http://www.hificollective.co.uk/b/bk6001c.html. I think . . . but
don't remember for sure . . . since it was probably 20 years since I last
looked at it . . . that they had a PCB layout for it in the handbook.
http://art-pipes.com/electronics/schematics.htm. The TDA part has complete
application info PLUS a PCB. Xmas in Sept.
NC means "no charge" = free. I have a tubed module measuring about 3-1/2
square that takes two 6CG7s. Came out of a Nipponese receiver, complete
with coils, diodes, etc. and the usual bad Jap grey caps. I think I took it
out of a Pioneer receiver but I don't remember the model #. I clipped the
wires going to it but it is easy to see what is B+, Gnd, Audio Out, and RF
in.

Well now, that's a step up in my fortunes!
My customer may prefer to pay me an extra $ for the tubed decoder,
and besides, I learn from the experience, and I'll document the work,
and post the results back to you all.
I have to know all about what I make; I am one of the only tube service
ppl here in this town.
I could easily decode what the tubes used in the decoder are trioding to do!!
But one could never work out the circuit used for a chip.
And it allows me to try 6DJ8; they are not bad where 6CG7
were used for signal work.
I designed and built my own decoder seen at
http://www.turneraudio.com.au/htmlwebpgs02/schemampxdecoder.htm
I think I spent a month foolin around until I got that design to work OK,
and also make use of the Trio parts which were in the receiver.
The original Trio made the stereo sound like it was coming down a
drain pipe.
I know I couldn't reproduce that effort unless I had the coils.
This is the problem when doing anything like this.

Post by Jon Yaeger
I'll send it with your choice of LM1800 or LM1870, which I believe I can get
from a local supplier, also NC. Hey, you don't charge me for technical
advice . . .

The LM1800 needs a tunable coil for the 19 kHz, but apparently not
on the LM1800N, which has a pot to tune the 19 kHz
I don't know about the LM1870.
A quality adjust multi turn cermet pot is easier to find than a bloomin coil.
My address is
Patrick Turner,
1 Adams Pl,
Watson,
ACT 2602,
Australia.
Regards,
Patrick Turner.

Shipped out today by USPS Airmail. You should have it in 4-7 days.

Jon

[Patrick Turner]

Post by Jon Yaeger
Shipped out today by USPS Airmail. You should have it in 4-7 days.
Jon

Thankyou Jon.

That will be an interesting puzzle to unravel.

It is sometimes hard to see how a tube decoder is ever going to compete with
the chip versions which seem to use several long tail pairs instead of diodes
and a detector matrix.
Most tube decoders use a transformer to drive the detector matrix.
I tried using a tube LTP, which works OK, but it needs some refinement.
I think the phase of the injected 38 kHz isn't exactly lined up with the phase
of the 19 kHz pilot tone, I have never played around with a phase shift network
to see what difference advancing or retarding the 38 kHz phase would make.
I also need at least another twin triode for output cathode followers and better
output filters.
The ripple F from the detection RC network from my LTP is 76 kHz , because two
phases of the same
38 kHz AM signals are being detected, one a negative going signal, L-R, and the
other a positive going.
signal -L+R.
If the ripple F is 76 kHz, its easy to filter out.

My set up uses a triggered locked oscillator for the 19 kHz, so that the 38 kHz is
at least
related exactly in frequency to the pilot tone.
Its not a phase lock loop type of set up, but it does seem to work OK.
I used a triode and a pentode for this function, but it could be also
done using 3 discrete transistors, because it doesn't matter what means one uses to
generate
a 38 kHz carrier, since it isn't part of the audio signal path.

Regards,

Patrick Turner.

[Jon Yaeger]

Post by Patrick Turner

Post by Sander deWaal

Post by Patrick Turner
I have the circuit for the Studio12, but is there anyone else
selling MPX kitsets?

http://users.otenet.gr/~athsam/stereo_decoder_3.htm using MC1310P
http://users.otenet.gr/~athsam/stereo_decoder_4.htm using LM1800N

The LM1800 is the basis of the Studio12 circuit shown at
http://werple.net.au/~kiewavly/Leak/stereo_dec3.gif
The one above has buffer opamps to do the de-emphasis,
but still no filters to clean out the 38 kHz switching artifacts.
I may well settle for using one of these chips on a bit of board,
but it means finding all the parts, doing my own board design with
solid wire links, and all that takes time.
A kitset of this size is a 1 hour soldering job.
Patrick Turner.

Post by Sander deWaal
http://rlocman.ru/en/out.htm
--
Sander deWaal
"SOA of a KT88? Sufficient."

I don't have time right now to research, but National Semi used to have
proto eval PCB for their MPX chips. Also try Rohm.


- Jon