"Dave Plowman (News)" wrote in message
...
In article i,

Keep an eye on Ebay - do a search and save that. You'll then get
emails if anything matching that search comes up. Those and PPM
movements do come up from time to time.

Thanks Dave. I did that a month ago.

Other thing might be to use the scale from a broken one with a more common
voltmeter of the same basic style and movement. Of course I realise a
*true* VU has a very special movement - but many fitted to UK equipment
were only suitable for line up on steady tone where the ballistics aren't
so important. Some BBC spec tape recorders, for example.

The application I have for these meters requires proper VU ballistics.
There are lots of cheap Taiwanese copies but many of them have not
even taken the trouble to get the scale right on the face plate:-)

The Ernest Turner is the best of
the best. They are very hard to find these days.

Indeed - the same applies the PPMs. The Ernest Turner movements are the
best too.

The PPM which interest me is not the BBC type, but the EMI/Decca
meter, on which the red scale starts at +8dBm and goes to +12dBm

Sifam seem to be a strange company - I contacted them about a
replacement or repair for the meter on a Ferrograph test set and got a
pretty unhelpful reply.

I got a spare meter from them for my Ferrograph RTS without any
difficulty (though this was some time ago)

Make contact with:

Long since sorted. Can't remember who I spoke to on the phone - the name
gets forgotten long before the bones of the conversation.

But did you get your replacement meter?

Incidentally, I OCR'd and re-printed manuals for both the RTS2 and ATU1
and have the files for them stored. Ended up with a rather higher quality
product than the original duplicated ones.

I have original manuals for both the RTS and ATU.
It's still a very useful piece of equipment.

Iain

On Wed, 06 Feb 2008 13:14:24 +0000, Audix wrote:

I know the Decca PPM and have a pair of them. Mine use Ernest Turner
703 movements, scaled from -30 to +18dB. The drive amps to go with
them are a custom Decca job too. I have also seen an Ernest Turner
early twin movement with Decca scales. I have never seen a formal
specification of the Decca PPM.

Not a BBC scale then? Remember the BBC engineering version of the
motto: "Nation shall peak 6 unto nation"

d

--
Pearce Consulting
http://www.pearce.uk.com

Don Pearce wrote:

Audix wrote:

I know the Decca PPM and have a pair of them. Mine use Ernest Turner
703 movements, scaled from -30 to +18dB. The drive amps to go with
them are a custom Decca job too. I have also seen an Ernest Turner
early twin movement with Decca scales. I have never seen a formal
specification of the Decca PPM.

Not a BBC scale then?

Doesn't sound like it. 48dB dynamic range on a meter is pretty good.

Graham

"Eeyore" wrote in message
...


Don Pearce wrote:

Audix wrote:

I know the Decca PPM and have a pair of them. Mine use Ernest Turner
703 movements, scaled from -30 to +18dB. The drive amps to go with
them are a custom Decca job too. I have also seen an Ernest Turner
early twin movement with Decca scales. I have never seen a formal
specification of the Decca PPM.

Not a BBC scale then?

Doesn't sound like it. 48dB dynamic range on a meter is pretty good.


And not the same as the EBU scale either, which is like the BBC one, but
calibrated in dB, from -22dB to +4dB, with 0dB equal to 6 on the BBC scale.

Yes, a 48dB dynamic range on a meter is impressive, but possibly less useful
in a broadcast environment.

David.

"Don Pearce" wrote in message
...
On Wed, 06 Feb 2008 13:14:24 +0000, Audix wrote:

I know the Decca PPM and have a pair of them. Mine use Ernest Turner
703 movements, scaled from -30 to +18dB. The drive amps to go with
them are a custom Decca job too. I have also seen an Ernest Turner
early twin movement with Decca scales. I have never seen a formal
specification of the Decca PPM.

Not a BBC scale then? Remember the BBC engineering version of the
motto: "Nation shall peak 6 unto nation"


I was told that the BBC type PPM was actually first
used by Decca. I have also seen this mentioned
somewhere on the web, by Tony Griffiths I think,
but I do not have a link.

But the Decca PPM as such had an Ernest Turner
meter with the red segment starting at +8dBm.
IIRC It had a rise time of 10mS and a slow decay
(2 secs) They was also a later faster
version with the peak level marked at +12dBm.

Iain

"Iain Churches" wrote in message
ti.fi...



But the Decca PPM as such had an Ernest Turner
meter with the red segment starting at +8dBm.
IIRC It had a rise time of 10mS and a slow decay
(2 secs) They was also a later faster
version with the peak level marked at +12dBm.


Is the Decca PPM actually marked in dBm, rather than just dB?.

David.

"David Looser" wrote in message
...
"Iain Churches" wrote in message
ti.fi...



But the Decca PPM as such had an Ernest Turner
meter with the red segment starting at +8dBm.
IIRC It had a rise time of 10mS and a slow decay
(2 secs) They was also a later faster
version with the peak level marked at +12dBm.


Is the Decca PPM actually marked in dBm, rather than just dB?.


It's 28 years since I saw one, but yes I am sure they
were calibrated in dBm I may have some photos of the Neves
in Studio II, and at Tollington Park, and the Decca mixer in
Studio III. I will try to find them. The meters in copying
and cutting rooms had a red line at +8dBm, but other
versions had a red segment from +8dBm and the later
faster meters in Remix II had the red segment starting
at +12dBm.

There must have been many hundreds of these meters
in use at Decca.

Iain

"Iain Churches" wrote in message
ti.fi...


"David Looser" wrote in message
...
"Iain Churches" wrote in message
ti.fi...



But the Decca PPM as such had an Ernest Turner
meter with the red segment starting at +8dBm.
IIRC It had a rise time of 10mS and a slow decay
(2 secs) They was also a later faster
version with the peak level marked at +12dBm.


Is the Decca PPM actually marked in dBm, rather than just dB?.


It's 28 years since I saw one, but yes I am sure they
were calibrated in dBm I may have some photos of the Neves
in Studio II, and at Tollington Park, and the Decca mixer in
Studio III. I will try to find them. The meters in copying
and cutting rooms had a red line at +8dBm, but other
versions had a red segment from +8dBm and the later
faster meters in Remix II had the red segment starting
at +12dBm.

There must have been many hundreds of these meters
in use at Decca.


Then this is yet another example of the audio industry's notorious
sloppiness with the use of the term "dBm". I'm sure that if a line-up tone
indicated "0dBm" on the meter an rms voltage of 0.7748V (0.7748V rms
dissipates 1mW in 600 ohm) was present at the line-out of the mixer. But
that doesn't mean that the meter was actually reading dBm with music signals
(rather than tone) or if the impedance presented to the mixer line-out was
other than exactly 600 ohm.

I would have expected better of Decca.

David.

David Looser wrote:

"Iain Churches" wrote in message
"David Looser" wrote in message
"Iain Churches" wrote in message


But the Decca PPM as such had an Ernest Turner
meter with the red segment starting at +8dBm.
IIRC It had a rise time of 10mS and a slow decay
(2 secs) They was also a later faster
version with the peak level marked at +12dBm.


Is the Decca PPM actually marked in dBm, rather than just dB?.


It's 28 years since I saw one, but yes I am sure they
were calibrated in dBm I may have some photos of the Neves
in Studio II, and at Tollington Park, and the Decca mixer in
Studio III. I will try to find them. The meters in copying
and cutting rooms had a red line at +8dBm, but other
versions had a red segment from +8dBm and the later
faster meters in Remix II had the red segment starting
at +12dBm.

There must have been many hundreds of these meters
in use at Decca.


Then this is yet another example of the audio industry's notorious
sloppiness with the use of the term "dBm". I'm sure that if a line-up tone
indicated "0dBm" on the meter an rms voltage of 0.7748V (0.7748V rms
dissipates 1mW in 600 ohm) was present at the line-out of the mixer. But
that doesn't mean that the meter was actually reading dBm with music signals
(rather than tone) or if the impedance presented to the mixer line-out was
other than exactly 600 ohm.

I would have expected better of Decca.

You mean dBu of course ! ;~)

Graham

"Iain Churches" wrote in message
ti.fi...


"David Looser" wrote in message
...
"Iain Churches" wrote in message
ti.fi...



But the Decca PPM as such had an Ernest Turner
meter with the red segment starting at +8dBm.
IIRC It had a rise time of 10mS and a slow decay
(2 secs) They was also a later faster
version with the peak level marked at +12dBm.


Is the Decca PPM actually marked in dBm, rather than just dB?.


It's 28 years since I saw one, but yes I am sure they
were calibrated in dBm I may have some photos of the Neves
in Studio II, and at Tollington Park, and the Decca mixer in
Studio III. I will try to find them. The meters in copying
and cutting rooms had a red line at +8dBm, but other
versions had a red segment from +8dBm and the later
faster meters in Remix II had the red segment starting
at +12dBm.

There must have been many hundreds of these meters
in use at Decca.

Iain



I believe the larger PPM instrument showing +12dB meter scale, still with
peak 4 as 0 line-up, it had no red segment - just white characters on black
b/g, was known as the European standard PPM. It still used virtually the
same meter driver cct on a card often available in those days from the
designers Audio Engineering of Soho.
Jim