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Re: Measure -2450?

 

Sorry yes its voltage. Its for testing the high voltage regulator in a 475. I cannot afford another meter or a $100 probe. The voltage divider idea may work.

--- In TekScopes@..., Bob Albert <bob91343@...> wrote:

Can you be more specific??? Are you measuring voltage?

If so, an ordinary Simpson 260 or Triplett 630 will do, as long as it doesn't need to be very accurate.

If you need precision you can cobble up a voltage divider and measure the values to calculate the result.?? Most meters go to 1000 V so you need to divide by maybe 3 or 5.

Bob

















??









Is there a way to take this reading without a 3k meter?
Polish 7000 clone on eBleed

[email protected]
 

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ugly and wayyy overpriced - but interesting!
english lettering....
Bernd
?
152-0177-01 tunnel diode for 485.

 

¿ªÔÆÌåÓý

Looking for Tek 152-0177-01 tunnel diode (10mA and 4pf) for my 485.

Also used in Tek products S53, 067-0587-01, 067-0580-00, 3T5, 3T6, 5S14N, 7D14, 7T11, 7T11A.

Gold DO-17 top hat style. Including postage to the UK.

Phil.
Re: Measure -2450?

 

It's the same size as the 80K-40, yellow instead of red, has the same 1 GOhm
input impedance when used with a 10 MOhm input meter, but rated only for 15
KV instead of 40 KV.

I don't really see why an 80K-40 wouldn't be useful in the same application
that the 80K-15 was made for. Or perhaps the 80K-40 came later with higher
rated insulation to 40 KV?

Joe

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...] On Behalf
Of Mark Wendt
Sent: Monday, March 04, 2013 4:25 AM
To: TekScopes@...
Subject: Re: [TekScopes] Measure -2450?

On 03/04/2013 01:13 AM, David wrote:
Fluke 80K-6 high voltage probes are inexpensive used and good to 6
kilovolts. They are designed to be used with a 10 megohm input
resistance multimeter which is standard. They only have 75 megohms of
input resistance though which may be a problem measuring many of the
CRT voltages like the grid or focus but will work fine for measuring
the cathode voltage which is regulated.
I knew probes could be used for a lot of things, but this is a new one on
me:

<
5539>

Mark


------------------------------------

Yahoo! Groups Links
Re: Measure -2450?

Mark Wendt
 

On 03/04/2013 07:35 AM, Bert Haskins wrote:
On 03/04/2013 05:24 AM, Mark Wendt wrote:
On 03/04/2013 01:13 AM, David wrote:
Fluke 80K-6 high voltage probes are inexpensive used and good to 6
kilovolts. They are designed to be used with a 10 megohm input
resistance multimeter which is standard. They only have 75 megohms of
input resistance though which may be a problem measuring many of the
CRT voltages like the grid or focus but will work fine for measuring
the cathode voltage which is regulated.
I knew probes could be used for a lot of things, but this is a new one
on me:

<>

Mark
No surprise, electrostatics can go to some pretty high voltages.

They can give you a nasty bite.
I'd never seen it called an Electronic Air Cleaner probe before. ;-)

Mark
Re: Measure -2450?

 

On 03/04/2013 05:24 AM, Mark Wendt wrote:
On 03/04/2013 01:13 AM, David wrote:
Fluke 80K-6 high voltage probes are inexpensive used and good to 6
kilovolts. They are designed to be used with a 10 megohm input
resistance multimeter which is standard. They only have 75 megohms of
input resistance though which may be a problem measuring many of the
CRT voltages like the grid or focus but will work fine for measuring
the cathode voltage which is regulated.
I knew probes could be used for a lot of things, but this is a new one
on me:

<>

Mark
No surprise, electrostatics can go to some pretty high voltages.

They can give you a nasty bite.


settings online go to:

Re: Measure -2450?

Mark Wendt
 

On 03/04/2013 01:13 AM, David wrote:
Fluke 80K-6 high voltage probes are inexpensive used and good to 6
kilovolts. They are designed to be used with a 10 megohm input
resistance multimeter which is standard. They only have 75 megohms of
input resistance though which may be a problem measuring many of the
CRT voltages like the grid or focus but will work fine for measuring
the cathode voltage which is regulated.
I knew probes could be used for a lot of things, but this is a new one on me:

<>

Mark
Re: Looking for TDS420(A) Power Supply

 

Hello Raymond
I have a power supply for tds 420A.
How much do you want to spend?
If you send in your faulty I may be able to repair it or sell you one for parts.
Thanks Jan Koria
Re: Measure -2450?

 

Fluke 80K-6 high voltage probes are inexpensive used and good to 6
kilovolts. They are designed to be used with a 10 megohm input
resistance multimeter which is standard. They only have 75 megohms of
input resistance though which may be a problem measuring many of the
CRT voltages like the grid or focus but will work fine for measuring
the cathode voltage which is regulated.

On Mon, 04 Mar 2013 04:41:16 -0000, "anson_williams@..."
<tractormananson@...> wrote:

Is there a way to take this reading without a 3k meter?
Re: Measure -2450?

Bob Albert
 

Can you be more specific?? Are you measuring voltage?

If so, an ordinary Simpson 260 or Triplett 630 will do, as long as it doesn't need to be very accurate.

If you need precision you can cobble up a voltage divider and measure the values to calculate the result.? Most meters go to 1000 V so you need to divide by maybe 3 or 5.

Bob


--- On Sun, 3/3/13, anson_williams@... wrote:

From: anson_williams@...
Subject: [TekScopes] Measure -2450?
To: TekScopes@...
Date: Sunday, March 3, 2013, 8:41 PM

?

Is there a way to take this reading without a 3k meter?

Measure -2450?

 

Is there a way to take this reading without a 3k meter?
Re: 549 with compresssed trace on right third of screen

 

I had a similar problem recently with Aerovox caps in my 564: one of these was defective, causing malfunction when erasing the storage screen.
After some checks, the only culprit was a 0.1uF 600V Aerovox capacitor. I don't have any ESR meter, but examining the erasure pulse with another scope, I immediately realized that the capacitor was lossy. I think ESR was fine, buth the dielectric absorption not.

On the component list, the caps was specified as metallized polyester.
I've temporarily replaced the defective one with two capacitor 0.1uF 630V ceramic FACON in parallel to compensate for major losses in ceramic type, waiting to have the right polyester type.

Oddly enough, since Matt states that only 549 Portland scopes used Areovox caps, my 564 is from Heerenveen, Netherlands.

Max

--- In TekScopes@..., "mattko87" <matt8@...> wrote:

Sorry, my fault.

0,5?F , (C335), that is right.

Heerenveen 549 has EROmet capicator, germany capicator.
But, Portland 549 has bad black areovox, replaced him and 549 run fine.

Best regards
Matt

--- In TekScopes@..., "mattko87" <matt8@> wrote:

Hi

pleas replaced 0,33?F Areovox capicator in Horz. amplifier.
This capicator ist bad.

I has repaired many 549, one from Nethersland (Heerenveen) has not this Problem, but Portland-549 has this problem awalys.

Best regards
matt
free in NYC: 7503, RM564, and TM506, for parts or repair

sipespresso
 

The 7503 needs work on the plug-in connectors. The side covers of the connectors need to be replaced. (This is a common failure mode and has been discussed in this forum.) I believe the scope is otherwise fine.

The TM506 works, but the power supply capacitors need to be replaced. It works with low-power plug-ins as is. Power-hungry plug-ins cause the DC supply to have unacceptable ripple, due to the bad capacitors.

The RM564, if I recall correctly, works in non-storage mode, but not in storage mode. I can check that. (I haven't powered it up in years.)

None of these items comes with plug-ins.

These items are available for local pickup in Manhattan, free of charge. Email me off-list if interested. thanks, -Kurt
067-0587-01 sold

 

fixture is sold..thanks

Jerry Massengale
Re: 549 with compresssed trace on right third of screen

 

Hi Keith

Areovox capicator has 0,9?F insteat 0,5?F, that is a typical paper-capicator-problem.

i think, 1N4148 is better, but i am not sure.

dirty contact, i use tuner 600 and q-tips.

Best regards.
matt

Thanks for guestbook in wellenkino.de :-)

--- In TekScopes@..., "keithostertag" <keitho@...> wrote:

Hi Matt-

Yes, thank you so much!

As you said, I replaced the Aerovox cap (C335) and that particular problem is resolved!

The bad cap did not show any leakage. On an ESR meter it measured much _lower_ than other similar type caps.

I accidentally broke diode D334 (clumsy) while replacing C335. I replaced it with a generic 1n4004, hope that's OK, seems to work.

Since you have experience with these 549's, are there any other specific common problems with them that you'd like to mention? Lots of switches and pots to clean...

Thanks,
Keith Ostertag

-
Re: 549 with compresssed trace on right third of screen

keithostertag
 

Hi Matt-

Yes, thank you so much!

As you said, I replaced the Aerovox cap (C335) and that particular problem is resolved!

The bad cap did not show any leakage. On an ESR meter it measured much _lower_ than other similar type caps.

I accidentally broke diode D334 (clumsy) while replacing C335. I replaced it with a generic 1n4004, hope that's OK, seems to work.

Since you have experience with these 549's, are there any other specific common problems with them that you'd like to mention? Lots of switches and pots to clean...

Thanks,
Keith Ostertag

-
My new 310A

 

Bought a 310A for little money, in perfect condition, optically and
electrically (what a sharp trace!), lucky me.

2 Questions:

It has serial number 013491, rectifier is with silicon diodes.
Anybody has an idea on which year this little oven was built?

Currently the transformer is wired for the "middle" tap. When I measure
my line voltage, it is 230V, with very little variation. Would it make
sense to wire the scope for 240V, to reduce voltage and heat stress?


Roland
Looking for TDS420(A) Power Supply

raymonddompfrank
 

Hi!
My TDS420A has a defective mains power supply.
Would any of you have one available from a parts mule?
AFAIK, PSU's in TDS420 and TDS420A are identical. True and any more models?

N.B. I'm living in Amsterdam, so shipment to The Netherlands.

Thanks,

Raymond
Re: 549 with compresssed trace on right third of screen

 

Sorry, my fault.

0,5?F , (C335), that is right.

Heerenveen 549 has EROmet capicator, germany capicator.
But, Portland 549 has bad black areovox, replaced him and 549 run fine.

Best regards
Matt

--- In TekScopes@..., "mattko87" <matt8@...> wrote:

Hi

pleas replaced 0,33?F Areovox capicator in Horz. amplifier.
This capicator ist bad.

I has repaired many 549, one from Nethersland (Heerenveen) has not this Problem, but Portland-549 has this problem awalys.

Best regards
matt
Re: Delta Standard for 130 L-C Meter has MINUS 3pF setting [1 Attachment]

Craig Sawyers
 

=================
How did Tek get the Delta Standard for the 130 L-C Meter to have a 0pF and a
MINUS 3pF value?
Exactly what is a negative capacitance and what is it good for?
See attached photo.
=================

The clue is in the word Delta, Dennis.

Craig
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