Tek 545B O'scope Fuse and Power

I prefer to use mild solvents actually, like alcohol/acetone. This is mainly for PCBs though, when it comes to cabinetry and shit I dunno, dish soap seems really good.

 

[Phil Allison]

"Trevor Wilson"

**I had one of these more than 30 years ago. It was hot, noisy, heavy and
an average performer. Do yourself a favour - buy a newer CRO. Even
something as old as a Tek 565b will be a revelation. You'll even be able
to move it about, without a forklift.

** Guess I am spoiled by my almost 30 year old BWD 821 ( dual trace 50MHz )
which weighs 7.8 kgs and consumes about 17 watts.



.... Phil

 

[Jeff Liebermann]

On Sun, 21 Apr 2013 16:33:45 +1000, "Phil Allison" <phil_a@tpg.com.au>
wrote:

"Jeff Liebermann"
"Phil Allison"

Liquid hand wash ( soap free & pH balanced ) is probably OK too.

I have my doubts about anything that has pH Balanced on the label.

** Yawnnnnnnnnnnnnnnnnnnnnn................

Compared to your usual critical comments, I presume that's a
compliment. Thanks.

The
term is completely meaningless and is mostly a marketing buzzword.
What is the pH of the soap being balanced against? What benefit does
this alleged balancing act have for the user? Too many unanswered
questions.

** It broadly refers to it being non alkalai - ie SOAP FREE !!!!!!!!

It can mean anything that marketing wants to claim. pH balanced may
sound like a technical term, but it's not.

That is, it will not irritate the skin on ones hands like ordinary soaps do
and washing liquid is infamous for.

Yep. No residual lye.

Been using them for 20 years myself.

I mostly use a home made Boraxo clone on my hands. About 95% borax
laundry powder, and 5% soap flakes. I use either Ivory brand soap,
shredded on a kitchen grater, or home made lye based soap where I used
too my lye and ended up with a pH=11. After about 10 years, it's now
down to about 9.0. No skin damage or drying (degreasing) evident
after about 40 years of use.

By the numbers:
Soap pH
Dove 7.0
Lever 2000 9.0
Camay 9.5
Dial 9.5
Irish Spring 9.5
Ivory 9.5
Palmolive 10.0
Zest 10.0

Work very nicely at cleaning my electric shaver too.

I use a brush.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Sat, 20 Apr 2013 23:48:07 -0700 (PDT), jurb6006@gmail.com wrote:

Very interesting.

You might be interested in what's in "pH balanced" shampoo. See:
<http://www.chagrinvalleysoapandsalve.com/idascorner/soappH.aspx>
at the bottom right of the page. It's a bit tricky to read, but it's
all there. Yech.

"Leave the rest alone as I assume that all the electrolytics
are bad and that it will need disassembly to replace those anyway.
"

You wouldn't believe how long some of those old caps can last.
When was the 561A made ? I had to only replace one. I had to
replace one in my 7603.

I haven't repaired too many old tube scopes. However, one of the
first that I repaired had to be torn apart three more times, each time
for yet another leaking or shorted electrolytic. After that
experience, I would do either a pre-emptive replacement of all the big
caps in the area or reform the caps if they looked marginal.
<http://www.angelfire.com/electronic/funwithtubes/Restore_cap.html>


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Phil Allison]

"Jeff Liebermann"
"Phil Allison"

Liquid hand wash ( soap free & pH balanced ) is probably OK too.

I have my doubts about anything that has pH Balanced on the label.

** Yawnnnnnnnnnnnnnnnnnnnnn................

Compared to your usual critical comments, I presume that's a
compliment.

** No it ain't.

The
term is completely meaningless and is mostly a marketing buzzword.
What is the pH of the soap being balanced against? What benefit does
this alleged balancing act have for the user? Too many unanswered
questions.

** It broadly refers to it being non alkali - ie SOAP FREE !!!!!!!!

It can mean anything that marketing wants to claim.

** Not when the words " soap free " are right there too.

Work very nicely at cleaning my electric shaver too.

I use a brush.

** FFS -

wot a painful, boring, literal, tiresome pedant !!!!!!!!!!!!!!!



..... Phil

 

"A "T 6.3" amp fuse is too big for a tube scope - "

Says it right on there if you look at the picture. IIRC the rule is to go by the marking on the unit if it differs from the manual.

I don't see a 6.25 amp as too big for that thing, I believe that is a body builder model with two handles and probably as many tubes as a 1950s color TV set. They pulled over 300 watts, alot of them almost 400.

I believe that scope is more than 50 tears old, I would say circa 1957. Even without transistors they did get a bit more efficient over the years. My old 561A doesn't pull as much as that dinosaur, and I think the only solid state in the is the rectifiers. not sure. but after some years tubes (valves) wound up with more gain so less of them were needed.

The OP should just put a damn seven amp fuse in it and try it. It does not have a fissionable material in it nor any explosives. If you are paranoid keep it away from the drapes, or hell just do it outside. Respect electriciy yes, but put it in perspective.

If it blows the fuse immediately the first thing is to disconnect all the rectifiers off the secondaries of the transformer to see if that's good. In fact if it powers up and has no trace it could still be the transformer. My 561A has leakage to the filament winding which shorts out the HV. I took a hi-pot little 6.3 volt transformer and wired it in, it works fine. However once insulation is breached.......... The nice thing now though is that the HV is no longer applied to that winding.

I remember that Tekronix had a lifetime warranty on their power transformers. I tried to get a replacement for mine and they would sell it to me but that is all. It's not like they didn''t have them. They basically said that they are no longer under the lifetime warranty. The rep also mention that they had alreacy been to court about it, it was like $150 or go fuck off.

Maybe I should look at a Gould next.

 

[Trevor Wilson]

On 4/21/2013 4:43 PM, Phil Allison wrote:

"Trevor Wilson"
Phil Allison wrote:

** So the thick plottens .......

Seems there is disagreement between the manual and the labelling on the
back.

A "T 6.3" amp fuse is too big for a tube scope - but an "F 6.3" amp
fuse
would be about right, given the inrush surge of the circa 200VA supply
transformer.

**Don't be too certain. My second CRO was an Hitachi copy of the Tek 545A.
It was a massive, heavy, noisy, hot bugger. So close, was the copy, that
the Tektronix service manual was perfectly suitable for fault-finding and
operational needs. FWIW, the only major difference between the Hitachi and
the Tek was Hitachi's use of 2% tolerance resistors throughout the entire
CRO (except for high precision areas). Tek used 10% or 20% tolerance
resistors throughout. The thing used a full RLC delay line with 20 or so
valves. The vertical amplifier valve filaments operated in a series string
of (as I best recall) 120 Volts DC. Regulation for various circuits
(including heaters) was via 3 X 6080 dual triodes. The thing ate them. It
had a 200mm fan in the back and consumed 500 Watts under normal operation.
Great in the workshop during Winter. Not so good during Summer. My
subsequent CRO was all solid state.

A 6.3AT fuse, for 117VAC is within possibility. I've got a manual for it
somewhere.


** Here is a pretty good pic of the insides of a 545B.

http://www.barrytech.com/tektronix/vintage/tek545bright.jpg

The AC tranny looks like it *might* be 500VA - but I expect Tek would use a
conservatively rated unit with a low temp rise.

If the OP would care to measure the primary resistance - I can say for sure.

**I found my 545A manual.

Power consumption is rated at 500 Watts. Weight is 65 pounds.

Fuse ratings:

6.25 Amp Slo-blo 3AG for 117VAC 50Hz
6 Amp fast blo 3AG for 117VAC 60Hz
3 Amp fast blo 3AG for 234VAC 60Hz
3 Amp slo-blo 3AG for 234VAC 50Hz

It's an interesting old CRO. I loved and hated mine in equal measure.
After I sold it, I bought a BWD, which I then swapped for a Tek 465B.
The 465B was boring. It did everything flawlessly and never gave me a
minute's trouble in more than 20 years.

The manual for the 545A occupies 50MB. I can post if you wish.



--
Trevor Wilson www.rageaudio.com.au

 

"What benefit does
this alleged balancing act have for the user? Too many unanswered

questions."

Anything too acidic or alkaline would be bad. However that doesn't mean something with the "proper" Ph for skin will be exactly right for this.

Of course if rinsed thoroughly anything from 6 to 8 should be just fine.

"The best example is pH balanced shampoo. What it does is suds only
over a very narrow range of pH. I don't recall the numbers, but it

specifically avoids the typically pH=5.5 of skin so that it does *NOT*
suds when first applied. Only after dilution with water, or a 2nd
application does the pH of the mix increase to roughly a neutral pH=7,
where it will produce suds. The obvious result is that users use
twice as much shampoo as they would with one that would suds at any pH
value. I suspect that hand and dishwashing soap may be similar, but I
haven't bothered to check.
"

Very interesting.

"Leave the rest alone as I assume that all the electrolytics
are bad and that it will need disassembly to replace those anyway.

"

You wouldn't believe how long some of those old caps can last. When was the 561A made ? I had to only replace one. I had to replace one in my 7603.

 

[Phil Allison]

"Trevor Wilson"

** Here is a pretty good pic of the insides of a 545B.

http://www.barrytech.com/tektronix/vintage/tek545bright.jpg

The AC tranny looks like it *might* be 500VA - but I expect Tek would
use a
conservatively rated unit with a low temp rise.

If the OP would care to measure the primary resistance - I can say for
sure.

**I found my 545A manual.

Power consumption is rated at 500 Watts. Weight is 65 pounds.

Fuse ratings:

6.25 Amp Slo-blo 3AG for 117VAC 50Hz
6 Amp fast blo 3AG for 117VAC 60Hz
3 Amp fast blo 3AG for 234VAC 60Hz
3 Amp slo-blo 3AG for 234VAC 50Hz

** Hmmmmm.....

Those numbers make me think the AC tranny is quite conservatively rated for
voltage and frequency.

Doing so, reduces the severity of inrush surges quite a bit.

BTW 1:

If you operate a 240V rated tranny on 120V - there is barely ANY inrush
surge at all.

( Electro caps in the PSU not withstanding. )

BTW 2:

The main source of inrush surge with tube gear is often due to all the tube
heaters being cold at switch on - particularly if the rectifiers are
vacuum tubes. The buggers take quite a time to warm up and increase in
resistance too.

But the 545B uses selenium diodes - right?


..... Phil

 

[Michael Black]

On Sun, 21 Apr 2013, Phil Allison wrote:

"Trevor Wilson"

** Here is a pretty good pic of the insides of a 545B.

http://www.barrytech.com/tektronix/vintage/tek545bright.jpg

The AC tranny looks like it *might* be 500VA - but I expect Tek would
use a
conservatively rated unit with a low temp rise.

If the OP would care to measure the primary resistance - I can say for
sure.

**I found my 545A manual.

Power consumption is rated at 500 Watts. Weight is 65 pounds.

Fuse ratings:

6.25 Amp Slo-blo 3AG for 117VAC 50Hz
6 Amp fast blo 3AG for 117VAC 60Hz
3 Amp fast blo 3AG for 234VAC 60Hz
3 Amp slo-blo 3AG for 234VAC 50Hz


** Hmmmmm.....

Those numbers make me think the AC tranny is quite conservatively rated for
voltage and frequency.

Doing so, reduces the severity of inrush surges quite a bit.

BTW 1:

If you operate a 240V rated tranny on 120V - there is barely ANY inrush
surge at all.

( Electro caps in the PSU not withstanding. )

BTW 2:

The main source of inrush surge with tube gear is often due to all the tube
heaters being cold at switch on - particularly if the rectifiers are
vacuum tubes. The buggers take quite a time to warm up and increase in
resistance too.

Which reminds me, there's a time delay in there. I don't see it on the

schematic (which is spread over many pages so I'm not sure which section
it's in), but I suddenly remember there's a point when it starts up when
things suddenly kick into operation. I seem to recall hearing the relay
kick in. Since I can't find that on the schematic, I'm not sure what it's
controlling.

But the 545B uses selenium diodes - right?

I have the B manual and they are listed as silicon. I think I would have
noticed selenium when I was inside the scope if they'd had them.

Michael

 

[Bill Gill]

On 4/21/2013 9:05 AM, Michael Black wrote:

On Sun, 21 Apr 2013, Phil Allison wrote:


"Trevor Wilson"

** Here is a pretty good pic of the insides of a 545B.

http://www.barrytech.com/tektronix/vintage/tek545bright.jpg

The AC tranny looks like it *might* be 500VA - but I expect Tek would
use a
conservatively rated unit with a low temp rise.

If the OP would care to measure the primary resistance - I can say for
sure.

**I found my 545A manual.

Power consumption is rated at 500 Watts. Weight is 65 pounds.

Fuse ratings:

6.25 Amp Slo-blo 3AG for 117VAC 50Hz
6 Amp fast blo 3AG for 117VAC 60Hz
3 Amp fast blo 3AG for 234VAC 60Hz
3 Amp slo-blo 3AG for 234VAC 50Hz


** Hmmmmm.....

Those numbers make me think the AC tranny is quite conservatively
rated for
voltage and frequency.

Doing so, reduces the severity of inrush surges quite a bit.

BTW 1:

If you operate a 240V rated tranny on 120V - there is barely ANY
inrush
surge at all.

( Electro caps in the PSU not withstanding. )

BTW 2:

The main source of inrush surge with tube gear is often due to all the
tube
heaters being cold at switch on - particularly if the rectifiers are
vacuum tubes. The buggers take quite a time to warm up and increase in
resistance too.

Which reminds me, there's a time delay in there. I don't see it on the
schematic (which is spread over many pages so I'm not sure which section
it's in), but I suddenly remember there's a point when it starts up when
things suddenly kick into operation. I seem to recall hearing the relay
kick in. Since I can't find that on the schematic, I'm not sure what
it's controlling.

But the 545B uses selenium diodes - right?

I have the B manual and they are listed as silicon. I think I would
have noticed selenium when I was inside the scope if they'd had them.

Michael
My admittedly 60 year old memory is that the A had selenium.

At work we replaced them with some special silicon replacements
when those became available. They were the same form factor so
we just had to remove the old ones and put in the new ones. I
wouldn't bet you could still get those, but it wouldn't be a
very big job to put in a terminal strip and use 2n2006, or whatever
is available now.

Bill

 

[Bill Gill]

On 4/21/2013 12:00 PM, Bill Gill wrote:

On 4/21/2013 9:05 AM, Michael Black wrote:
On Sun, 21 Apr 2013, Phil Allison wrote:


"Trevor Wilson"

** Here is a pretty good pic of the insides of a 545B.

http://www.barrytech.com/tektronix/vintage/tek545bright.jpg

The AC tranny looks like it *might* be 500VA - but I expect Tek would
use a
conservatively rated unit with a low temp rise.

If the OP would care to measure the primary resistance - I can say for
sure.

**I found my 545A manual.

Power consumption is rated at 500 Watts. Weight is 65 pounds.

Fuse ratings:

6.25 Amp Slo-blo 3AG for 117VAC 50Hz
6 Amp fast blo 3AG for 117VAC 60Hz
3 Amp fast blo 3AG for 234VAC 60Hz
3 Amp slo-blo 3AG for 234VAC 50Hz


** Hmmmmm.....

Those numbers make me think the AC tranny is quite conservatively
rated for
voltage and frequency.

Doing so, reduces the severity of inrush surges quite a bit.

BTW 1:

If you operate a 240V rated tranny on 120V - there is barely ANY
inrush
surge at all.

( Electro caps in the PSU not withstanding. )

BTW 2:

The main source of inrush surge with tube gear is often due to all the
tube
heaters being cold at switch on - particularly if the rectifiers are
vacuum tubes. The buggers take quite a time to warm up and increase in
resistance too.

Which reminds me, there's a time delay in there. I don't see it on the
schematic (which is spread over many pages so I'm not sure which section
it's in), but I suddenly remember there's a point when it starts up when
things suddenly kick into operation. I seem to recall hearing the relay
kick in. Since I can't find that on the schematic, I'm not sure what
it's controlling.

But the 545B uses selenium diodes - right?

I have the B manual and they are listed as silicon. I think I would
have noticed selenium when I was inside the scope if they'd had them.

Michael
My admittedly 60 year old memory is that the A had selenium.
At work we replaced them with some special silicon replacements
when those became available. They were the same form factor so
we just had to remove the old ones and put in the new ones. I
wouldn't bet you could still get those, but it wouldn't be a
very big job to put in a terminal strip and use 2n2006, or whatever
is available now.

Bill

Whoops! 1n2006 not 2n2006. If there should happen to be a 2n2006

available it probably wouldn't make a good high voltage rectifier.
Bill

 

On Sun, 21 Apr 2013 18:20:42 +1000, Trevor Wilson
<trevor@SPAMBLOCKrageaudio.com.au> wrote:

On 4/21/2013 4:43 PM, Phil Allison wrote:
"Trevor Wilson"
Phil Allison wrote:

** So the thick plottens .......

Seems there is disagreement between the manual and the labelling on the
back.

A "T 6.3" amp fuse is too big for a tube scope - but an "F 6.3" amp
fuse
would be about right, given the inrush surge of the circa 200VA supply
transformer.

**Don't be too certain. My second CRO was an Hitachi copy of the Tek 545A.
It was a massive, heavy, noisy, hot bugger. So close, was the copy, that
the Tektronix service manual was perfectly suitable for fault-finding and
operational needs. FWIW, the only major difference between the Hitachi and
the Tek was Hitachi's use of 2% tolerance resistors throughout the entire
CRO (except for high precision areas). Tek used 10% or 20% tolerance
resistors throughout. The thing used a full RLC delay line with 20 or so
valves. The vertical amplifier valve filaments operated in a series string
of (as I best recall) 120 Volts DC. Regulation for various circuits
(including heaters) was via 3 X 6080 dual triodes. The thing ate them. It
had a 200mm fan in the back and consumed 500 Watts under normal operation.
Great in the workshop during Winter. Not so good during Summer. My
subsequent CRO was all solid state.

A 6.3AT fuse, for 117VAC is within possibility. I've got a manual for it
somewhere.


** Here is a pretty good pic of the insides of a 545B.

http://www.barrytech.com/tektronix/vintage/tek545bright.jpg

The AC tranny looks like it *might* be 500VA - but I expect Tek would use a
conservatively rated unit with a low temp rise.

If the OP would care to measure the primary resistance - I can say for sure.

**I found my 545A manual.

Power consumption is rated at 500 Watts. Weight is 65 pounds.

Fuse ratings:

6.25 Amp Slo-blo 3AG for 117VAC 50Hz
6 Amp fast blo 3AG for 117VAC 60Hz
3 Amp fast blo 3AG for 234VAC 60Hz
3 Amp slo-blo 3AG for 234VAC 50Hz

It's an interesting old CRO. I loved and hated mine in equal measure.
After I sold it, I bought a BWD, which I then swapped for a Tek 465B.
The 465B was boring. It did everything flawlessly and never gave me a
minute's trouble in more than 20 years.

The manual for the 545A occupies 50MB. I can post if you wish.
On the advice of several folks here and in the basic electronics group

I bought a used 465B 'scope several years ago. You are correct, if
exitement is fixing a 'scope, the 465B is quite boring.
Eric

 

[Michael A. Terrell]

Michael Black wrote:

On Sun, 21 Apr 2013, Phil Allison wrote:

But the 545B uses selenium diodes - right?

I have the B manual and they are listed as silicon. I think I would have
noticed selenium when I was inside the scope if they'd had them.

The 545A manual says silicon, as well.

 

[Michael A. Terrell]

Phil Allison wrote:

"Michael Black"

Of course the fuse takes care of the whole thing, it's in the primary to
the power transformer. F601, it's a 6amp fast-blo 3AG fuse for 120vac
operation (3ampts if running off 240v).

** As marked on the rear of the scope - the fuse needs to be a "slow blow"
type.

It's a standard glass fuse, you should be able to get them anywhere.

** Well, anywhere that has available a good range of fuses for electronic
equipment.

Slow blow fuses are commonly stamped or marked with a "T" before the amp
rating.

MDL is used in US equipment 14"*1-1/4" slow blow.

So look for a " T6.3A " fuse in 3AG size ( or 32 x 6.3 mm) - though such as
high value seems wrong for a tube scope.

If you use a standard "fast " fuse, it may well blow at switch on.

Not on 60 Hz.

 

[Michael A. Terrell]

etpm@whidbey.com wrote:

I bought a used 465B 'scope several years ago. You are correct, if
exitement is fixing a 'scope, the 465B is quite boring.

Not true. A radio station engineer bought three from DMRO that didn't
work. I managed to repair two, by scraping the third. Too many
critical parts were NLA.

 

[Michael A. Terrell]

jurb6006@gmail.com wrote:

I prefer to use mild solvents actually, like alcohol/acetone. This is mainly for PCBs though, when it comes to cabinetry and shit I dunno, dish soap seems really good.

We used a citrus based, water soluble solvent in a commercial
stainless steel dishwasher to clean boards at the Microdyne factory.

 

[Trevor Wilson]

On 4/21/2013 9:13 PM, Phil Allison wrote:

"Trevor Wilson"

** Here is a pretty good pic of the insides of a 545B.

http://www.barrytech.com/tektronix/vintage/tek545bright.jpg

The AC tranny looks like it *might* be 500VA - but I expect Tek would
use a
conservatively rated unit with a low temp rise.

If the OP would care to measure the primary resistance - I can say for
sure.

**I found my 545A manual.

Power consumption is rated at 500 Watts. Weight is 65 pounds.

Fuse ratings:

6.25 Amp Slo-blo 3AG for 117VAC 50Hz
6 Amp fast blo 3AG for 117VAC 60Hz
3 Amp fast blo 3AG for 234VAC 60Hz
3 Amp slo-blo 3AG for 234VAC 50Hz


** Hmmmmm.....

Those numbers make me think the AC tranny is quite conservatively rated for
voltage and frequency.

Doing so, reduces the severity of inrush surges quite a bit.

BTW 1:

If you operate a 240V rated tranny on 120V - there is barely ANY inrush
surge at all.

( Electro caps in the PSU not withstanding. )

BTW 2:

The main source of inrush surge with tube gear is often due to all the tube
heaters being cold at switch on - particularly if the rectifiers are
vacuum tubes. The buggers take quite a time to warm up and increase in
resistance too.

But the 545B uses selenium diodes - right?

**I doubt it. The CRO does use a time delay at switch-on.


--
Trevor Wilson www.rageaudio.com.au

 

[Trevor Wilson]

On 4/25/2013 6:36 AM, Noel Keith wrote:

Alright. I've done a whole lot in a short ammount of time. Cleaning
out the Oscilloscope was no simple task, but It's done. Dried and
everything. And, as luck would have it, my fuses arrived today. Now's
the really tricky part: finding the right fusecap.

Not so much as finding the right one, but making a temporary one
until I can find a replacement one. I've also brushed up on my
electronics vernacular, so I should have a much better idea of what
you guys are talking about now as well. Alright, so I haven't given
it much thought yet, but I've read in a couple of places that you can
make your own fusecap using a machine screw and some electrical tape.
Not sure on how WELL this would work, but I have plenty of
replacement fuses if something goes wrong so I'm not too worried. Is
there an easier way to do this? I mean, I can assume the head of the
machine screw would be on the outside while the other end would be
holding the fuse in place. Hmmm... Any better ideas?

**Install a new fuseholder.

--
Trevor Wilson www.rageaudio.com.au

 

[Noel Keith]

Alright. I've done a whole lot in a short ammount of time. Cleaning out the Oscilloscope was no simple task, but It's done. Dried and everything. And, as luck would have it, my fuses arrived today. Now's the really tricky part: finding the right fusecap.

Not so much as finding the right one, but making a temporary one until I can find a replacement one. I've also brushed up on my electronics vernacular, so I should have a much better idea of what you guys are talking about now as well. Alright, so I haven't given it much thought yet, but I've read in a couple of places that you can make your own fusecap using a machine screw and some electrical tape. Not sure on how WELL this would work, but I have plenty of replacement fuses if something goes wrong so I'm not too worried. Is there an easier way to do this? I mean, I can assume the head of the machine screw would be on the outside while the other end would be holding the fuse in place. Hmmm...
Any better ideas?