Wartime Minicsope oscilloscope , any info/sources ?

N

N_Cook

Guest
http://home.graffiti.net/diverse:graffiti.net/miniscope9.jpg

Made for ultra portability fits in an 8x11x 2.5 inch case when the thyratron
and vibrator are removed from the chassis and stowed near the hinge. What
war time use was there for such a small 'scope, with in-the-field 12V supply
capability?
War finish presumably means the off white enamel rather than black crackle
finish.
Plate on the brown casing lid
Miniscope
Miniature C/R oscilloscope
Pattern No 58259

Stencilled labels on the case are
R.L. 4
and No 1

Presumably somewhere would have info on the pattern number.
Even using "-dr who" googling does not find anything on Miniscope or that
pattern number, plenty on the 6K25 thyratron but nothing on 9 pin VR91,
10E/92 voltage regulator? or 9 pin CRT
VCR 522, 10E/787, Design Inspected CRT 4
(shattered probably when the shoulder carrying strap broke and corner brace
broke off and split occured in the "suitcase" )
no other valves,
also Masteradio G650 12V vibrator, military trident symbol in a couple of
places , after an A on the VR91 and before a Z on the CRT
side panels missing, someone has crudely bodged in pot .


http://home.graffiti.net/diverse:graffiti.net/miniscope1.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope2.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope3.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope4.jpg
specs etc on hinge-down, prop-up plate
http://home.graffiti.net/diverse:graffiti.net/miniscope5.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope7.jpg



--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
VR91 would seem a pentode
http://www.radiomuseum.org/tubes/tube_vr91.html

CRTm some info
www.radiomuseum.org/tubes/tube_vcr522.html


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
N_Cook wrote:
Made for ultra portability fits in an 8x11x 2.5 inch case
Click to expand...
Well that's certainly a clever bit of kit.

Keep us posted if you find out anything about it.

Jeff
 
What a neat piece of history! Never seen one before so can't add any info.
Pity about the broken CRT - is it replaceable? Also, I love the words "time
base" on the label - takes me back to those days of yesteryear!

BTW, the VR91/EF50 is an RF pentode - I once had an old TRF, one channel TV
(Pye 19T) that used several of them in the RF strip. One of my first
"serious" tube(valve) proejcts was to build an ITV converter from scrap WW2
parts to convert circa 180 MHz ITV to the circa 42.5 MHz (vision) and 41.5
MHz (sound) antenna input of the Pye 19T (I forget the actual frequencies.)
Cheers,
Roger

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:gjipsp$dq1$1@news.motzarella.org...
VR91 would seem a pentode
http://www.radiomuseum.org/tubes/tube_vr91.html

CRTm some info
www.radiomuseum.org/tubes/tube_vcr522.html


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
Click to expand...
 
On Thu, 1 Jan 2009 16:10:05 -0000, "N_Cook" <diverse@tcp.co.uk> wrote:

VR91 would seem a pentode
Click to expand...
equivalent EF50 (often red coating) was used a lot in early TRF televisions.

Bit of info on the 6K25 - probably used for a timebase:-
http://www.domino405.co.uk/documents/Ultra_V71_Series.pdf

--
Geo
 
engineer <analogdino@rogers.com> wrote in message
news:gjirin$33b$1@analogdino.motzarella.org...
What a neat piece of history! Never seen one before so can't add any
info.
Pity about the broken CRT - is it replaceable? Also, I love the words
"time
base" on the label - takes me back to those days of yesteryear!

BTW, the VR91/EF50 is an RF pentode - I once had an old TRF, one channel
TV
(Pye 19T) that used several of them in the RF strip. One of my first
"serious" tube(valve) proejcts was to build an ITV converter from scrap
WW2
parts to convert circa 180 MHz ITV to the circa 42.5 MHz (vision) and 41.5
MHz (sound) antenna input of the Pye 19T (I forget the actual
frequencies.)
Cheers,
Roger

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:gjipsp$dq1$1@news.motzarella.org...

VR91 would seem a pentode
http://www.radiomuseum.org/tubes/tube_vr91.html

CRTm some info
www.radiomuseum.org/tubes/tube_vcr522.html


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
Click to expand...

I picked it up at a "silent key" disposal at a carboot sale. Inheritors had
no knowldege about it. The valves etc may not be what was originally in
there of course.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
I picked it up at a "silent key" disposal at a carboot sale. Inheritors had
no knowldege about it. The valves etc may not be what was originally in
there of course.
Click to expand...
Looks like a "Malvern" variant from this page:
http://www.thevalvepage.com/testeq/scope.htm
 
Mike <bj_blazkowicz@cyberdude.com> wrote in message
news:ps0ql4tik03gegtd1plvp2n80judqefbog@4ax.com...
I picked it up at a "silent key" disposal at a carboot sale. Inheritors
had
no knowldege about it. The valves etc may not be what was originally in
there of course.

Looks like a "Malvern" variant from this page:
http://www.thevalvepage.com/testeq/scope.htm
Click to expand...

Thanks for that
I've used or repaired nearly all those on bottom 3 rows and a few of the
earlier

http://www.thevalvepage.com/testeq/gec/miniscope/miniscope.htm
GEC one looks very similar externally, especially the prop plate
The chassis dimensions are similar, this one 8 x 6.5 x 2.25 inches but
valves and internals are look earlier.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:gjip7o$5m8$1@news.motzarella.org...
http://home.graffiti.net/diverse:graffiti.net/miniscope9.jpg

Made for ultra portability fits in an 8x11x 2.5 inch case when the
thyratron
and vibrator are removed from the chassis and stowed near the hinge. What
war time use was there for such a small 'scope, with in-the-field 12V
supply
capability?
War finish presumably means the off white enamel rather than black crackle
finish.
Plate on the brown casing lid
Miniscope
Miniature C/R oscilloscope
Pattern No 58259

Stencilled labels on the case are
R.L. 4
and No 1

Presumably somewhere would have info on the pattern number.
Even using "-dr who" googling does not find anything on Miniscope or that
pattern number, plenty on the 6K25 thyratron but nothing on 9 pin VR91,
10E/92 voltage regulator? or 9 pin CRT
VCR 522, 10E/787, Design Inspected CRT 4
(shattered probably when the shoulder carrying strap broke and corner
brace
broke off and split occured in the "suitcase" )
no other valves,
also Masteradio G650 12V vibrator, military trident symbol in a couple of
places , after an A on the VR91 and before a Z on the CRT
side panels missing, someone has crudely bodged in pot .


http://home.graffiti.net/diverse:graffiti.net/miniscope1.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope2.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope3.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope4.jpg
specs etc on hinge-down, prop-up plate
http://home.graffiti.net/diverse:graffiti.net/miniscope5.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope7.jpg
Click to expand...
VR91 / EF50 was used in many wartime radios and early radar units (PPI and
pulse position). I owned a '1392 ex RAF vhf control tower receiver for many
years, and that was full of them.

Arfa
 
On Thu, 1 Jan 2009 18:30:16 -0000, "N_Cook" <diverse@tcp.co.uk> wrote:

Mike <bj_blazkowicz@cyberdude.com> wrote in message
news:ps0ql4tik03gegtd1plvp2n80judqefbog@4ax.com...


I picked it up at a "silent key" disposal at a carboot sale. Inheritors
had
no knowldege about it. The valves etc may not be what was originally in
there of course.

Looks like a "Malvern" variant from this page:
http://www.thevalvepage.com/testeq/scope.htm


Thanks for that
I've used or repaired nearly all those on bottom 3 rows and a few of the
earlier

http://www.thevalvepage.com/testeq/gec/miniscope/miniscope.htm
GEC one looks very similar externally, especially the prop plate
The chassis dimensions are similar, this one 8 x 6.5 x 2.25 inches but
valves and internals are look earlier.
Click to expand...
Yep, it looks like an earlier version of the GEC unit. Maybe a
prototype?
 
Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:HJ87l.8517$kt6.594@newsfe19.ams2...
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:gjip7o$5m8$1@news.motzarella.org...
http://home.graffiti.net/diverse:graffiti.net/miniscope9.jpg

Made for ultra portability fits in an 8x11x 2.5 inch case when the
thyratron
and vibrator are removed from the chassis and stowed near the hinge.
What
war time use was there for such a small 'scope, with in-the-field 12V
supply
capability?
War finish presumably means the off white enamel rather than black
crackle
finish.
Plate on the brown casing lid
Miniscope
Miniature C/R oscilloscope
Pattern No 58259

Stencilled labels on the case are
R.L. 4
and No 1

Presumably somewhere would have info on the pattern number.
Even using "-dr who" googling does not find anything on Miniscope or
that
pattern number, plenty on the 6K25 thyratron but nothing on 9 pin VR91,
10E/92 voltage regulator? or 9 pin CRT
VCR 522, 10E/787, Design Inspected CRT 4
(shattered probably when the shoulder carrying strap broke and corner
brace
broke off and split occured in the "suitcase" )
no other valves,
also Masteradio G650 12V vibrator, military trident symbol in a couple
of
places , after an A on the VR91 and before a Z on the CRT
side panels missing, someone has crudely bodged in pot .


http://home.graffiti.net/diverse:graffiti.net/miniscope1.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope2.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope3.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope4.jpg
specs etc on hinge-down, prop-up plate
http://home.graffiti.net/diverse:graffiti.net/miniscope5.jpg
http://home.graffiti.net/diverse:graffiti.net/miniscope7.jpg




VR91 / EF50 was used in many wartime radios and early radar units (PPI and
pulse position). I owned a '1392 ex RAF vhf control tower receiver for
many
years, and that was full of them.

Arfa
Click to expand...
I downloaded the GEC schematic from
http://www.thevalvepage.com/download/download.php?file=miniscope.pdf&dir=gec
but substantially different, except 4V and 6.3V heaters agree with
VCR 522
and VR91.
Looks as though I'll have to get/derive the
CRT VCR 722/ CV1522 or related E4103/B/4 / CV320 / CV967 / CV335 pinout and
maybe de-topologize for the schematic.
But I'd really like to find out what sort of use it was put to, most likely
tech
museum or forum to try ?
Very large print , 1 inch high letters "R.L.4" = radio location unit 4 ?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
Of course a broken CRT makes it easy to determine pinning.
As broke unpowered the heater is still there, all 4 X,Y plates exposed and
A3 so just leaves A2 and grid undetermined without destroying the envelope
more.
155mm long, 1.5 in diam, and 7 out of 9 pins agrees with GEC 4103/B/4 with
1.1KV pda and 4V heater.
And I have the pinning for the 6K25 and pentode.
I may scan in the board edges, as is with added valve pin labels , and
multi-photo before undoing and trying to unravel the schematic while trying
to find out about its likely in service use.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
On Jan 1, 4:08 pm, "N_Cook" <dive...@tcp.co.uk> wrote:
Of course a broken CRT makes it easy to determine pinning.
As broke unpowered the heater is still there, all 4 X,Y plates exposed and
A3 so just leaves A2 and grid undetermined without destroying the envelope
more.
155mm long, 1.5 in diam, and 7 out of 9 pins agrees with GEC 4103/B/4 with
1.1KV pda and 4V heater.
And I have the pinning for the 6K25 and pentode.
I may scan in the board edges, as is with added valve pin labels , and
multi-photo before undoing and trying to unravel the schematic while trying
to find out about its likely in service use.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list onhttp://home.graffiti.net/diverse:graffiti.net/
Click to expand...
Would someone at the, if I remember from a visit to London 10 years
ago, British War Museum be able to help you?
 
hr(bob) hofmann@att.net <hrhofmann@att.net> wrote in message
news:90eca134-9137-42f4-9b44-731da02cfa5e@z28g2000prd.googlegroups.com...
On Jan 1, 4:08 pm, "N_Cook" <dive...@tcp.co.uk> wrote:
Of course a broken CRT makes it easy to determine pinning.
As broke unpowered the heater is still there, all 4 X,Y plates exposed and
A3 so just leaves A2 and grid undetermined without destroying the envelope
more.
155mm long, 1.5 in diam, and 7 out of 9 pins agrees with GEC 4103/B/4 with
1.1KV pda and 4V heater.
And I have the pinning for the 6K25 and pentode.
I may scan in the board edges, as is with added valve pin labels , and
multi-photo before undoing and trying to unravel the schematic while
trying
to find out about its likely in service use.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list
onhttp://home.graffiti.net/diverse:graffiti.net/
Click to expand...

Would someone at the, if I remember from a visit to London 10 years
ago, British War Museum be able to help you?

******

I'd thought of contacting Kew ,PRO, national archives, but the Imperial War
Museum makes sense as well.
I'm a bit concerned with the use of the word pattern before the number 53259
in that it may relate to the "samsonite" case rather than scope although
etched on to the metal plate refering to C/R oscilloscope, I will take
another pic later . Perhaps there is a GEC archive somewhere other than Kew
and the war museum.



--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
hr(bob) hofmann@att.net <hrhofmann@att.net> wrote in message
news:90eca134-9137-42f4-9b44-731da02cfa5e@z28g2000prd.googlegroups.com...
On Jan 1, 4:08 pm, "N_Cook" <dive...@tcp.co.uk> wrote:
Of course a broken CRT makes it easy to determine pinning.
As broke unpowered the heater is still there, all 4 X,Y plates exposed and
A3 so just leaves A2 and grid undetermined without destroying the envelope
more.
155mm long, 1.5 in diam, and 7 out of 9 pins agrees with GEC 4103/B/4 with
1.1KV pda and 4V heater.
And I have the pinning for the 6K25 and pentode.
I may scan in the board edges, as is with added valve pin labels , and
multi-photo before undoing and trying to unravel the schematic while
trying
to find out about its likely in service use.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list
onhttp://home.graffiti.net/diverse:graffiti.net/
Click to expand...

Would someone at the, if I remember from a visit to London 10 years
ago, British War Museum be able to help you?

*****

GEC/Marconi archives site
http://www.marconicalling.com/front.htm
seems to be defunct

I will try contacting
http://www.theiet.org/about/libarc/index.cfm
and am aware of a very active retired members branch around Portsmouth
http://www.theiet.org/local/uk/south/solent/rm-section.cfm
who may be able to help as I seem to remember GEC had a site in Pompey


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
I've put a page together on
http://home.graffiti.net/diverse:graffiti.net/miniscope.htm
with a pic of the case top with the "R.L.4" stencil

and will add to when I've found out any more


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
In article <gjip7o$5m8$1@news.motzarella.org>,
"N_Cook" <diverse@tcp.co.uk> wrote:

http://home.graffiti.net/diverse:graffiti.net/miniscope9.jpg

Made for ultra portability fits in an 8x11x 2.5 inch case when the thyratron
and vibrator are removed from the chassis and stowed near the hinge. What
war time use was there for such a small 'scope, with in-the-field 12V supply
capability?
War finish presumably means the off white enamel rather than black crackle
finish.
Plate on the brown casing lid
Miniscope
Miniature C/R oscilloscope
Pattern No 58259

Stencilled labels on the case are
R.L. 4
and No 1

Presumably somewhere would have info on the pattern number.
Click to expand...
I don't know if you found this page or not, but it may be of help.
There's a claim to a service manual for (some model of) the GEC
miniscope, among other details. I have no idea if it's the same basic
design or not, but they do look at least related.

http://www.thevalvepage.com/testeq/gec/miniscope/miniscope.htm

Presumably it's the civilian finish for the one on that page, what with
fancier knobs and such.

--
Andrew Erickson

"He is no fool who gives what he cannot keep to gain that which he cannot
lose." -- Jim Elliot
 
CUTE, I want one!!! I sold my Jackson 1" 'scope a few years ago and regret
it.

John H.
 
On Fri, 2 Jan 2009 12:25:35 -0000, "N_Cook" <diverse@tcp.co.uk> wrote:

I've put a page together on
http://home.graffiti.net/diverse:graffiti.net/miniscope.htm
with a pic of the case top with the "R.L.4" stencil

and will add to when I've found out any more
Click to expand...
Assuming that it's military, I think the "R" would stand for Radio.
The "L" would stand for Laboratory (test & calibration).

http://www.hypertools.com/nomenclature.html
 
On Fri, 2 Jan 2009 23:07:57 -0500, "HagstAr"
<yonnyKILL@SPAMMERSatt.net> wrote:

CUTE, I want one!!! I sold my Jackson 1" 'scope a few years ago and regret
it.

John H.

You can bid on one now. Starting at Ł49.99
Click to expand...

http://cgi.ebay.co.uk/GEC-Miniscope-vintage-Oscilloscope_W0QQitemZ160307519137QQcmdZViewItemQQimsxZ20090101?IMSfp=TL090101112002r15921
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top