On Mon, 04 Jun 2012 21:54:11 +0000, Hank wrote:

Heathkit made a Q-meter kit that was patterned after
the Boonton, but simplified. I had one of these for years, and got
quite a bit of use out of it, but the 260A is a step up in capability
and accuracy.


Hank

Since you mentioned the Heathkit unit, I have one that I haven't done
anything with since I don't have the special inductor to calibrate it. I
also don't have any way to measure an ordinary inductor to use as a
substitute. Do you know of some other way to calibrate it?

Thanks,

--
Jim Mueller

To get my real email address, replace wrongname with dadoheadman.
Then replace nospam with fastmail. Lastly, replace com with us.

Jim Mueller wrote:
On Mon, 04 Jun 2012 21:54:11 +0000, Hank wrote:

Heathkit made a Q-meter kit that was patterned after
the Boonton, but simplified. I had one of these for years, and got
quite a bit of use out of it, but the 260A is a step up in capability
and accuracy.

Since you mentioned the Heathkit unit, I have one that I haven't done
anything with since I don't have the special inductor to calibrate it. I
also don't have any way to measure an ordinary inductor to use as a
substitute. Do you know of some other way to calibrate it?

Purchase a reference inductor from J. W. Miller?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Jim Mueller wrote:
On Mon, 04 Jun 2012 21:54:11 +0000, Hank wrote:

Heathkit made a Q-meter kit that was patterned after
the Boonton, but simplified. I had one of these for years, and got
quite a bit of use out of it, but the 260A is a step up in capability
and accuracy.


Hank

Since you mentioned the Heathkit unit, I have one that I haven't done
anything with since I don't have the special inductor to calibrate it. I
also don't have any way to measure an ordinary inductor to use as a
substitute. Do you know of some other way to calibrate it?

Thanks,

When I got mine I sent a few of my coils out to another guy to measure
them. Then I used his findings to set up my Heathkit. Everything was
pretty close from the get go.

-Bill

In article om,
Jim Mueller wrote:
On Mon, 04 Jun 2012 21:54:11 +0000, Hank wrote:

Heathkit made a Q-meter kit that was patterned after
the Boonton, but simplified. I had one of these for years, and got
quite a bit of use out of it, but the 260A is a step up in capability
and accuracy.


Hank

Since you mentioned the Heathkit unit, I have one that I haven't done
anything with since I don't have the special inductor to calibrate it. I
also don't have any way to measure an ordinary inductor to use as a
substitute. Do you know of some other way to calibrate it?

If you've got the unit, you can use a 455 khz IF transformer to check
out its functionality. Most of these used in AA5's had coil Q around
100. There are probably ten or twenty different ways to getting a
reasonable calibration, depending on what other test equipment you
have available and your knowledge and skill in methodologies for using
them. Also consider what your intended use of the Q-meter is. For
getting front-end coils and IF transformers in a receiver you are
bringing back to life, your primary need is to find coil inductance
and whether the Q is "reasonable" or "not reasonable." There is a
good discussion of Q measurements and a section on Q meters and their
vagaries in Terman and Pettit "Electronic Measurements" (2nd ed.,
McGraw-Hill, 1952). What that makes clear is that absolute
measurements with a Q meter have enough error that they're only
indicative of in-circuit performance.

Your first calibration point is to set up the injection oscillator.
That's a frequency measurement, traceable to NIST through WWV.
The second calibration point is the tracking of the resonating
capacitor to the panel calibrations.
The third calibration point is the oscillator injection voltage
across the metering resistor.
The fourth calibration point is the voltage developed across the coil
at resonance. "Q" is the ratio of that voltage to the injection
voltage.

If you've got something like an RF VTVM available, you can measure the
two voltages directly. You probably are not going to want to go
through the gyrations needed to refer anything but the frequency
measurement back to NIST.

A quick search on the net with Duckduckgo came up with this link:
http://www.jamminpower.com/main/260A.html
It's got links to 260A user and calibration manuals. The Heath unit
is a cheap knock-off of the Boonton design, so the Boonton material
generally applies to it. The Heath unit is quite adequate for
repair bench work. The unit I had did yeoman service before I got the
first 260A. While mine came with the standard coil, it got its
calibration checks with nothing better than a Tek 547 scope and
Tek signal generator, with a variety of coils used as a cross-check.

Hank

"Hank" wrote in message
...
In article
,
Richard Knoppow wrote:

"Clutter" wrote in message
...
On 05/19/2012 12:08 PM, Richard Knoppow wrote:
"Renan

wrote in message
...

Hi everyone, I am looking for a VR-300 ,( 95 - 130
volts,
60Hz Voltage
Stibilizer ) used In BOONTON Q Meter 190A. Please, If
available, let me
know the value. Thank you in advance!


There are two mailing lists that may be of help.
One
is
the Agilent-Hewlett-Packard list and the other is the
Boonton list.

http://groups.yahoo.com/group/hp_agilent_equipment/

http://groups.yahoo.com/group/Boonton/


Thanks for the Yahoo groups info. I didn't know about
those two.
I joined the Boonton group as I have a couple of 260A's
both in
need of repair to some degree. Now if I can just find
some
time
to work on them...


There are probably a few people on one or the other
of
those groups who know the 260A well. At -hp- all the
Boonton stuff was done by a couple of specialists who did
nothing else. I think the 260A is reasonably easy to get
operational, the 250A RX meter was a bear to get
calibrated
and the older 160A Q-Meter requires a special tube which
was
selected. Boonton liked using selected tubes, one of the
202 series RF generators used three tubes of the same type
but selected for different characteristics. A royal PITA.
There have been a couple of other Q meters made but
the
260A is still an excellent instrument. The trouble is
that
most people now have no idea of what they do or how to use
one.

I have to chuckle at the idea that people don't know the
value of
Boonton Q meters and the 250A RX bridge. I cut my teeth
on the 160A
and 190A Q meters and the 250A when I went to work for
James Millen in
1956.

Forty years later, when equipping a bench for doing some
serious work
with boatanchors, I located a 260A---got it working, but
it was a
cosmetic horror, so when someone gave me a non-working but
cosmetically clean 260A with a tentative diagnosis of a
burned-out
thermocouple, I took it. However, it turned out that the
thermocouple
was not burned out, just had a bad solder connection at
one end of the
heater wire.

The 260A (as I recall, a 1953 redesign of the mid-1930's
160A) is not
particularly difficult to work on. Biggest problem I
found with both
was poor contact with the oscillator turret pins and open
oscillator
coils. The open coils all were breakage at the turret
pins, very easy
fix. But the brass pins and contacts took abrasive work
to get them
to make contact. DeOxit D-5 didn't touch them.

The 160A used a selected 45 tube for the oscillator, and
the
thermocouple burned out quite easily. The 260A uses an
off-the-shelf
tube--5763 as I recall---so that component is a
plug-and-play
replacement. The 260A thermocouple is much more robust.
I've
forgotten what was in the 190A, though I've been inside
all of them at
one time or another. The VTVM tube is selected in all of
them.

Boonton supported these units with excellent manuals which
go into
great detail about how they can be use. That's true of
the RX Bridge
as well. The Q-meters are not at all difficult to
calibrate by the
procedures given by Boonton.

When push comes to shove, there is nothing like a good
Q-meter when
dealing with boatanchor front-end and IF coils. One
strand of broken
Litzendraht drop the Q of a coil significantly, and having
a Q-meter
available to get the exact capacitor needed for a
silver-mica failure
makes life very simple. Of course, a Measurements
Megacycle Meter or
Millen Grid Dip complement them nicely, but aren't
substitutes.

The 250A RX Bridge was, I think, a bit daunting for
1930's/1940's
radio EE's. The Chief Engineer at Millen, Wade Caywood,
bought one
for the company, and spent quite a bit of time
experimenting with how
best to use it. Mine came out from under a table at a
hamfest---not
working, but looked brand new, and when the guy said he
wanted $20 for
it I swapped cash for the bridge and immediately took it
out to my
car. All that was wrong with it was that the Amperex
ballast tube was
open, so no voltage to the IF strip heaters. I just used
wire-wound
resistors to set the voltage. I don't recall having to
fix any
oscillator problems, but the mica dialectric in the little
capacitor
at the front of the bridge had to be reglued in place
(Pliobond). The
bridge was calibrated after it was assembled, so you
really do not
want to fuss with it.

I'd have to say that to get real mileage out of these
boxes,
particularly the RX bridge, you've got to know a bit more
than you're
going to learn from the ARRL Handbooks or Fred Terman's
texts.

I have used the Marconi Q-meter, which also uses a special
(read
"unobtainium") tube, but you have to have both of the
power
oscillators that go with it. Heathkit made a Q-meter kit
that was
patterned after the Boonton, but simplified. I had one of
these for
years, and got quite a bit of use out of it, but the 260A
is a step up
in capability and accuracy.

I'm not sure what Boonton was thinking when they put the
voltage
stabilizers in the Q-meters and the ballast in the RX
bridge. Unless
your primary power is seriously off-voltage, I don't see
that they are
needed.

Hank


The 190A uses a diode rather than a thermocouple. The
diode runs, I think, in its square-law region and is the
only tube in the instrument that was selected. I don't know
what measurements were made on this tube. The meter scale
will not track properly if the tube characteristics are not
right. However, the tubes are very long lived and can not
be burned out.
The thermocouple in the 260-A is much harder to damage
than the one in the 160-A but one must still use some care
in setting the oscillator level.
Both handbooks have pretty good texts on Q and its
significance and additional literature was available from
Boonton, most, if not all, of which is on the web.
A couple of standard coils for the meters are useful
for checking but overall calibration, as you say, does not
need them. Working coils are very easy to make.
The RX meter requires some study, it is not a general
purpose bridge. Mainly, the Q-Meters are intended for
relatively high-Q circuits and the RX-Meter for low-Q
circuits. The RX meter is excellent for measuring the RF
characteristics of resistors.
All three of these guys, but especially the RX-Meter
are true boatanchors:-)



--
Richard Knoppow
Los Angeles
WB6KBL

I would like to thank all ones that added valuable informations concerning to these wonders of electronics, developed in a part of time where art merges with the knowledge.
With respect to the voltage stabilizer used in 190A, q meter, which I cited earlier in this topic, I decided to open it, it was not difficult as it sounds! wrapped in a black sealant ( asphalt derived) I found a transformer with reactor coupled to it and a large oil capacitor (1.75 Uf / 660 vac, Aerovox) the capacitor was swollen and in short circuit , as was expected because age. I replaced it by 4x 470uF / 630volts, polyester metallized,When I turned on the electric supply 114volts 60Hertz , the output was 127 volts, I have found information about this type of transformer in the excellent book (Transforming and Inductor Design Handbook by Colonel Wm. T. McLyman) recalculated the capacitor based on the measured voltages, found 1.58 Uf, then removed one , leaving a capacitor of approximately 1.41Uf ( 3x 470 Uf ), the output is now 116 volts.
The Q meter is running ok , I hope to get a standard coil to check it.

Renan
PP7HP
Maceió - AL , Brazil

"Renan Cysneiros"
wrote in message
...

Richard Knoppow;791746 Wrote:
"Hank" wrote in message
...-
In article
,
Richard Knoppow wrote:-

"Clutter" wrote in message
...-
On 05/19/2012 12:08 PM, Richard Knoppow wrote:
"Renan

wrote in message
...

Hi everyone, I am looking for a VR-300 ,( 95 - 130
volts,
60Hz Voltage
Stibilizer ) used In BOONTON Q Meter 190A. Please, If
available, let me
know the value. Thank you in advance!



I would like to thank all ones that added valuable
informations
concerning to these wonders of electronics, developed in a
part of time
where art merges with the knowledge.
With respect to the voltage stabilizer used in 190A, q
meter, which
I cited earlier in this topic, I decided to open it, it
was not
difficult as it sounds! wrapped in a black sealant (
asphalt derived) I
found a transformer with reactor coupled to it and a large
oil capacitor
(1.75 Uf / 660 vac, Aerovox) the capacitor was swollen and
in short
circuit , as was expected because age. I replaced it by 4x
470uF /
630volts, polyester metallized,When I turned on the
electric supply
114volts 60Hertz , the output was 127 volts, I have found
information
about this type of transformer in the excellent book
(Transforming and
Inductor Design Handbook by Colonel Wm. T. McLyman)
recalculated the
capacitor based on the measured voltages, found 1.58 Uf,
then removed
one , leaving a capacitor of approximately 1.41Uf ( 3x 470
Uf ), the
output is now 116 volts.
The Q meter is running ok , I hope to get a standard coil
to check
it.

Renan
PP7HP
Maceió - AL , Brazil

Who made the transformer in your 190? I have a 190
where the transformer runs hot. It may be that the cap is
getting leaky. It still regulates at the right voltage but
is very hot.


--
Richard Knoppow
Los Angeles
WB6KBL



--
Renan Cysneiros

Thanks for the suggestions and especially the links to more information.
I haven't had time to read them yet but I did download and save them for
when that time comes. A quick glance at them already gave ideas on how
to get my meter going without a standard inductor, although that method
would be much easier!


--
Jim Mueller

To get my real email address, replace wrongname with dadoheadman.
Then replace nospam with fastmail. Lastly, replace com with us.

Dear Richard,
My transformer was manufactured by ACME electronic. Usually this type of transformer, works hot due to saturated core,” but not super hot”.
As you reported, I suspect that the cap. is leaking, it's worth a look, even due to aging. I recommend use of capacitors in parallel, at least 3 for splitting the current (1Kvolt rated), 3 x 470nF, works fine in mine.
I got my 190A via ebay in hong kong two months ago, and after about 20 min. turned on, the pilot lamp extinguished and the equipment comes down.
Now, its ok.

Greetings !

Renan – PP7HP
Maceió , Brazil

"Renan Cysneiros"
wrote in message
...

Richard Knoppow;791819 Wrote:
"Renan Cysneiros"
wrote in message
...-

Richard Knoppow;791746 Wrote:-
"Hank" wrote in message
...-
In article
,
Richard Knoppow wrote:-

"Clutter" wrote in message
...-
On 05/19/2012 12:08 PM, Richard Knoppow wrote:
"Renan

wrote in message
...

Hi everyone, I am looking for a VR-300 ,( 95 - 130
volts,
60Hz Voltage
Stibilizer ) used In BOONTON Q Meter 190A. Please, If
available, let me
know the value. Thank you in advance!
-


I would like to thank all ones that added valuable
informations
concerning to these wonders of electronics, developed in
a
part of time
where art merges with the knowledge.
With respect to the voltage stabilizer used in 190A, q
meter, which
I cited earlier in this topic, I decided to open it, it
was not
difficult as it sounds! wrapped in a black sealant (
asphalt derived) I
found a transformer with reactor coupled to it and a
large
oil capacitor
(1.75 Uf / 660 vac, Aerovox) the capacitor was swollen
and
in short
circuit , as was expected because age. I replaced it by
4x
470uF /
630volts, polyester metallized,When I turned on the
electric supply
114volts 60Hertz , the output was 127 volts, I have found
information
about this type of transformer in the excellent book
(Transforming and
Inductor Design Handbook by Colonel Wm. T. McLyman)
recalculated the
capacitor based on the measured voltages, found 1.58 Uf,
then removed
one , leaving a capacitor of approximately 1.41Uf ( 3x
470
Uf ), the
output is now 116 volts.
The Q meter is running ok , I hope to get a standard coil
to check
it.

Renan
PP7HP
Maceió - AL , Brazil
-
Who made the transformer in your 190? I have a 190
where the transformer runs hot. It may be that the cap is
getting leaky. It still regulates at the right voltage
but
is very hot.


--
Richard Knoppow
Los Angeles
WB6KBL
-


--
Renan Cysneiros -

Dear Richard,
My transformer was manufactured by ACME electronic.
Usually this
type of transformer, works hot due to saturated core,” but
not super
hot”.
As you reported, I suspect that the cap. is leaking, it's
worth a
look, even due to aging. I recommend use of capacitors in
parallel, at
least 3 for splitting the current (1Kvolt rated), 3 x
470nF, works fine
in mine.
I got my 190A via ebay in hong kong two months ago, and
after about
20 min. turned on, the pilot lamp extinguished and the
equipment comes
down.
Now, its ok.

Greetings !

Renan – PP7HP
Maceió , Brazil

Thanks Renan, I don't remember who made the transformer
in my 190A. I will have a look and see about getting into
it. It gets hot enough to melt the potting material. The
transformer in my 260A Q-Meter is cool to the touch even
after its been running for an extended time which makes me
thing this one should be the same.


--

--
Richard Knoppow
Los Angeles
WB6KBL