Topics

Help restoring a 547 scope

felix_cantor@...
 

Hello everyone! New guy in town here ;)

I just purchased an used 547 that I want to fully restore.

It was in working condition when I bought it but the traces and the trigger systems didn`t work that well. Channel B didn`t even trigger.
The interior was quite dusty and dirty, so I decided to give it a bath as per the manual recommendation. I covered the transformer and took great care not to wet it and also not to wet the high voltage section for the CRT. After the wash I placed it at the sun for around 2 days and kept it in the house for another 4 days or so before trying to turn it on again. After that I plugged the unit to a current limiter just in case something was wrong with the scope after the wetting, and it seemingly was broken! The light was at full bright when I turned on the scope though the scope remained without any sign of being powered up. So I guess there is a short right at the beginning of the power section....

I`m some sort of an amateur so I`m not so sure how to proceed right now without screwing up the scope anymore. I`ve build a few tube amplifiers and restored a few old test equipment, so I know the basics really.

Any help will be very much appreciated.

Thanks.
F.

 

The 547 has like a 30 second power on delay so you have to wait that
long.

What do you mean "the light as at full bright"?

The place to start is checking the power supply voltages. Some of
them are hundreds of volts so care is needed.

On Thu, 11 Jan 2018 09:31:37 -0800, you wrote:

Hello everyone! New guy in town here ;)

I just purchased an used 547 that I want to fully restore.

It was in working condition when I bought it but the traces and the trigger systems didn`t work that well. Channel B didn`t even trigger.
The interior was quite dusty and dirty, so I decided to give it a bath as per the manual recommendation. I covered the transformer and took great care not to wet it and also not to wet the high voltage section for the CRT. After the wash I placed it at the sun for around 2 days and kept it in the house for another 4 days or so before trying to turn it on again. After that I plugged the unit to a current limiter just in case something was wrong with the scope after the wetting, and it seemingly was broken! The light was at full bright when I turned on the scope though the scope remained without any sign of being powered up. So I guess there is a short right at the beginning of the power section....

I`m some sort of an amateur so I`m not so sure how to proceed right now without screwing up the scope anymore. I`ve build a few tube amplifiers and restored a few old test equipment, so I know the basics really.

Any help will be very much appreciated.

Thanks.
F.

Pete Lancashire
 

When you finished washing it, do you use compressed dry air (oil free) and
have a fan or something to keep the air moving all the time ?

What is the wattage of the lamp ?

Is your line voltage 120V or 240V ?

Did you try turning it on with all the tubes pulled ?

Is the Amperite switch open when cold ?

-pete

On Wed, Jan 17, 2018 at 6:51 PM, David Hess <@DWH> wrote:

The 547 has like a 30 second power on delay so you have to wait that
long.

What do you mean "the light as at full bright"?

The place to start is checking the power supply voltages. Some of
them are hundreds of volts so care is needed.

On Thu, 11 Jan 2018 09:31:37 -0800, you wrote:

Hello everyone! New guy in town here ;)

I just purchased an used 547 that I want to fully restore.

It was in working condition when I bought it but the traces and the
trigger systems didn`t work that well. Channel B didn`t even trigger.
The interior was quite dusty and dirty, so I decided to give it a bath as
per the manual recommendation. I covered the transformer and took great
care not to wet it and also not to wet the high voltage section for the
CRT. After the wash I placed it at the sun for around 2 days and kept it in
the house for another 4 days or so before trying to turn it on again. After
that I plugged the unit to a current limiter just in case something was
wrong with the scope after the wetting, and it seemingly was broken! The
light was at full bright when I turned on the scope though the scope
remained without any sign of being powered up. So I guess there is a short
right at the beginning of the power section....

I`m some sort of an amateur so I`m not so sure how to proceed right now
without screwing up the scope anymore. I`ve build a few tube amplifiers and
restored a few old test equipment, so I know the basics really.

Any help will be very much appreciated.

Thanks.
F.


Morris Odell
 

I wouldn't bother with a lamp current limiter in series, especially as it seems to have been working already before it was washed. Just make sure the right size fuse is in there and let 'er rip. The fan should start straight away and after what will seem like a long wait for the time delay relay you should hear a click and the scope should come alive. Let us know what happens next :-)

Morris

felix_cantor@...
 

On Wed, Jan 17, 2018 at 06:51 pm, David Hess wrote:


The 547 has like a 30 second power on delay so you have to wait that
long.

What do you mean "the light as at full bright"?

The place to start is checking the power supply voltages. Some of
them are hundreds of volts so care is needed.
Thanks for the response,

I mean that the bulb from the current limiter was fully bright when i turned on the scope, it didn´t dim at all... and the green lamp from the scope stayed off.

felix_cantor@...
 
Edited

Hey there!

On Wed, Jan 17, 2018 at 06:56 pm, Pete Lancashire wrote:


When you finished washing it, do you use compressed dry air (oil free) and
have a fan or something to keep the air moving all the time ?
nope... i just leaved it at the sunlight in the garden (it is windy here). After I started this thread i placed the scope for another three days at the sun, now i need to try turning it on again

What is the wattage of the lamp ?
100watts

Is your line voltage 120V or 240V ?
220V

Did you try turning it on with all the tubes pulled ?
nope

Is the Amperite switch open when cold ?
thats the k600 bulb? if so then yes.

-pete
Thank you!

felix_cantor@...
 

On Thu, Jan 18, 2018 at 03:02 am, Morris Odell wrote:


I wouldn't bother with a lamp current limiter in series, especially as it
seems to have been working already before it was washed. Just make sure the
right size fuse is in there and let 'er rip. The fan should start straight
away and after what will seem like a long wait for the time delay relay you
should hear a click and the scope should come alive. Let us know what happens
next :-)

Morris
I´m kinda scared of trying that... because with the current limiter the fan did nothing, the scope remained dead... dunno, maybe i should take the risk

felix_cantor@...
 

... I really appreciate your help fellas! Have a great day.

Chuck Harris
 

Relatively pure water is a relatively high impedance uhmmm? Load.

Simply washing a scope is unlikely to cause the scope to draw
excess amounts of current, unless you filled the transformer full
of water. You said that you didn't.

I would put my faith in the scope's fuse, and simply plug it in
and turn it on. If the fuse blows, figure out why.

-Chuck Harris

felix_cantor via Groups.Io wrote:

On Wed, Jan 17, 2018 at 06:51 pm, David Hess wrote:


The 547 has like a 30 second power on delay so you have to wait that
long.

What do you mean "the light as at full bright"?

The place to start is checking the power supply voltages. Some of
them are hundreds of volts so care is needed.
Thanks for the response,

I mean that the bulb from the current limiter was fully bright when i turned on the scope, it didn´t dim at all... and the green lamp from the scope stayed off.

Chuck Harris
 

The 547 draws a lot more than 100W in normal operation.
It will *not* start up with a 100W bulb in series.

If you really want to use a bulb as a safety fuse, you
are going to have to use more like 500W worth of bulbs.

-Chuck Harris

felix_cantor via Groups.Io wrote:

Hey there!

On Wed, Jan 17, 2018 at 06:56 pm, Pete Lancashire wrote:


When you finished washing it, do you use compressed dry air (oil free) and
have a fan or something to keep the air moving all the time ?
nope... i just leaved it at the sunlight in the garden (it is windy here). After I started this thread i placed the scope for another three days at the sun, now i need to try turning it on again

What is the wattage of the lamp ?
100watts

Is your line voltage 120V or 240V ?
220V

Did you try turning it on with all the tubes pulled ?
nope

Is the Amperite switch open when cold ?
thats the k600 bulb? if so then yes.

-pete
Thank you!

felix_cantor@...
 

On Thu, Jan 18, 2018 at 07:58 am, Chuck Harris wrote:


The 547 draws a lot more than 100W in normal operation.
It will *not* start up with a 100W bulb in series.

If you really want to use a bulb as a safety fuse, you
are going to have to use more like 500W worth of bulbs.

-Chuck Harris
Hey there Chuck!

Thanks for you input.

Even the fan will do nothing? ok will try without the current limiter right now.... scary.

felix_cantor@...
 

ok.... ignorance is the mother of all mistakes. It worked!

god! i love this scope.... the trace is so sharp! Amazing.

now i need to fix all the other issues.

felix_cantor@...
 

ok now some observations:

-It works much better than before the wash, the trace much more stable though it still deflects a little.... has some sort of vertical quick random deflection. But i guess it can be that some transistors need to have their legs cleaned. Seems like there is a bad contact somewhere.

-Time Base B still doesnt trigger.

-At first the trace appears super bright and it cant be adjusted with the intensity control, after a few seconds it dims a bit and the intensity control starts working.

-also the first inch of the trace is a little dimmer than the rest with the intensity control adjusted for nice visible trace, if I adjust it brighter then all the trace appear with the same intensity.


Those are the problems I acknowledge so far.

Sorry for my english.
All the best.

Chuck Harris
 

There is about 100W worth of filament current alone.
The fan will do nothing... and is probably dry of
lubrication anyway.

You need to dry your scope fully. The easiest way
to do that is to put a 60W light bulb in the vertical
plugin area, followed by a computer sized muffin fan.
Install the scope's side covers, and drape a towel
over the scope.

Let your scope dry this way for a few days.

After it is good and dry, plug your scope in, and see
what happens.

-Chuck Harris

felix_cantor via Groups.Io wrote:

On Thu, Jan 18, 2018 at 07:58 am, Chuck Harris wrote:


The 547 draws a lot more than 100W in normal operation.
It will *not* start up with a 100W bulb in series.

If you really want to use a bulb as a safety fuse, you
are going to have to use more like 500W worth of bulbs.

-Chuck Harris

Dave Seiter
 

Yeah, sometimes you just have to plug it in and go.  Waiting for the relay to kick in can seem like it takes forever!
It is a great scope!
-Dave

From: felix_cantor via Groups.Io <felix_cantor=yahoo.com@groups.io>
To: TekScopes@groups.io
Sent: Thursday, January 18, 2018 8:24 AM
Subject: Re: [TekScopes] Help restoring a 547 scope

ok.... ignorance is the mother of all mistakes. It worked!

god! i love this scope.... the trace is so sharp! Amazing.

now i need to fix all the other issues.

donald collie
 

Hi Dave,
Sphere Research Corporation have a document available from their website by
Tek, on how to troubleshoot their `scopes - you might like to read it.
Don`t let this `scope beat you, is the correct attitude, and remember :
most faults are simple - you can see or smell them. Are you sure your
`scope is completely dry? I wash my equipment that I import from eBay in a
bath of hot water, and detergent, rinse in hot pure water, and then dry in
front of a fan heater at about 60 degrees celcius, the hottest you can hold
your hand on, for at least 6 hours, preferably overnight. I usually clear
the faults before washing, as washing can provoke faults. Expect multiple
faults in a piece of equipment this age.Your `scope may have the imfamous
"Black Beauty" paper capacitors in it - these go leaky, and are best
replaced. They are recognised by their shiny [now shiny - you`ve cleaned
them!] black plastic cases. These are best replaced by polyester types. You
have a trace! Good! then you have no serious faults. If the `scopes
performance changes with time : Disconnect from the mains, and dry it out
some more. Make a wind tunnel of a cardboard box, and fan heater, so the
whole instrument gets hot, but not too hot. I think you were wise not to
wet the power transformer - I had a transformer fail once after washing.
Next thing i`d ckeck is the various HT`s for correct voltage, using a
meter, and for ripple/noise, using another `scope. This `scope can kill you
, so be careful. If you have a tube checker, I`d then check all the tubes,
because if the PSU`s aren`t 100%, or you have even 1 doubtful tube, your
pushing it up hill, to find a component fault, so to speak, I`ve just done
a 475 - it had leaky restorer diodes, and 2 defective transistors, which
fortunately weren`t soldered in, buy rather socketed. With determination,
patience, and the humility to ask those who have walked this road before
you, your `scope will be in factory condition sooner than you think. I have
a 547 sitting in storage. Perhaps i`ll start on it soon. What goes wrong
with the 547? The group will tell you.
Good luck, and all patience and determination to you!
Cheers!.....................................................................................................................Don
Collie ZL4GX

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On Fri, Jan 19, 2018 at 1:03 PM, Dave Seiter <d.seiter@...> wrote:

Yeah, sometimes you just have to plug it in and go. Waiting for the relay
to kick in can seem like it takes forever!
It is a great scope!
-Dave

From: felix_cantor via Groups.Io <felix_cantor=yahoo.com@groups.io>
To: TekScopes@groups.io
Sent: Thursday, January 18, 2018 8:24 AM
Subject: Re: [TekScopes] Help restoring a 547 scope

ok.... ignorance is the mother of all mistakes. It worked!

god! i love this scope.... the trace is so sharp! Amazing.

now i need to fix all the other issues.







Dave Seiter
 

Ummm, I'm not the OP, and have been through more scopes than I care to admit; just making a comment.
-Dave

From: donald collie <donaldbcollie@...>
To: TekScopes@groups.io
Sent: Thursday, January 18, 2018 4:47 PM
Subject: Re: [TekScopes] Help restoring a 547 scope

Hi Dave,
Sphere Research Corporation have a document available from their website by
Tek, on how to troubleshoot their `scopes - you might like to read it.
Don`t let this `scope beat you, is the correct attitude, and remember :
most faults are simple - you can see or smell them. Are you sure your
`scope is completely dry? I wash my equipment that I import from eBay in a
bath of hot water, and detergent, rinse in hot pure water, and then dry in
front of a fan heater at about 60 degrees celcius, the hottest you can hold
your hand on, for at least 6 hours, preferably overnight. I usually clear
the faults before washing, as washing can provoke faults. Expect multiple
faults in a piece of equipment this age.Your `scope may have the imfamous
"Black Beauty" paper capacitors in it - these go leaky, and are best
replaced. They are recognised by their shiny [now shiny - you`ve cleaned
them!] black plastic cases. These are best replaced by polyester types. You
have a trace! Good! then you have no serious faults.  If the `scopes
performance changes with time : Disconnect from the mains, and dry it out
some more. Make a wind tunnel of a cardboard box, and fan heater, so the
whole instrument gets hot, but not too hot. I think you were wise not to
wet the power transformer - I had a transformer fail once after washing.
Next thing i`d ckeck is the various HT`s for correct voltage, using a
meter, and for ripple/noise, using another `scope. This `scope can kill you
, so be careful. If you have a tube checker, I`d then check all the tubes,
because if the PSU`s aren`t 100%, or you have even 1 doubtful tube, your
pushing it up hill, to find a component fault, so to speak,  I`ve just done
a 475 - it had leaky restorer diodes, and 2 defective transistors, which
fortunately weren`t soldered in, buy rather socketed. With determination,
patience, and the humility to ask those who have walked this road before
you, your `scope will be in factory condition sooner than you think. I have
a 547 sitting in storage. Perhaps i`ll start on it soon. What goes wrong
with the 547? The group will tell you.
Good luck, and all patience and determination to you!
Cheers!.....................................................................................................................Don
Collie ZL4GX

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On Fri, Jan 19, 2018 at 1:03 PM, Dave Seiter <d.seiter@...> wrote:

Yeah, sometimes you just have to plug it in and go.  Waiting for the relay
to kick in can seem like it takes forever!
It is a great scope!
-Dave

      From: felix_cantor via Groups.Io <felix_cantor=yahoo.com@groups.io>
  To: TekScopes@groups.io
  Sent: Thursday, January 18, 2018 8:24 AM
  Subject: Re: [TekScopes] Help restoring a 547 scope

ok.... ignorance is the mother of all mistakes. It worked!

god! i love this scope.... the trace is so sharp! Amazing.

now i need to fix all the other issues.







donald collie
 

Sorry Dave, the blurb was, of course, meant for Felix.
Cheers!...........................................................................................Don
C.

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On Fri, Jan 19, 2018 at 1:53 PM, Dave Seiter <d.seiter@...> wrote:

Ummm, I'm not the OP, and have been through more scopes than I care to
admit; just making a comment.
-Dave

From: donald collie <donaldbcollie@...>
To: TekScopes@groups.io
Sent: Thursday, January 18, 2018 4:47 PM
Subject: Re: [TekScopes] Help restoring a 547 scope

Hi Dave,
Sphere Research Corporation have a document available from their website by
Tek, on how to troubleshoot their `scopes - you might like to read it.
Don`t let this `scope beat you, is the correct attitude, and remember :
most faults are simple - you can see or smell them. Are you sure your
`scope is completely dry? I wash my equipment that I import from eBay in a
bath of hot water, and detergent, rinse in hot pure water, and then dry in
front of a fan heater at about 60 degrees celcius, the hottest you can hold
your hand on, for at least 6 hours, preferably overnight. I usually clear
the faults before washing, as washing can provoke faults. Expect multiple
faults in a piece of equipment this age.Your `scope may have the imfamous
"Black Beauty" paper capacitors in it - these go leaky, and are best
replaced. They are recognised by their shiny [now shiny - you`ve cleaned
them!] black plastic cases. These are best replaced by polyester types. You
have a trace! Good! then you have no serious faults. If the `scopes
performance changes with time : Disconnect from the mains, and dry it out
some more. Make a wind tunnel of a cardboard box, and fan heater, so the
whole instrument gets hot, but not too hot. I think you were wise not to
wet the power transformer - I had a transformer fail once after washing.
Next thing i`d ckeck is the various HT`s for correct voltage, using a
meter, and for ripple/noise, using another `scope. This `scope can kill you
, so be careful. If you have a tube checker, I`d then check all the tubes,
because if the PSU`s aren`t 100%, or you have even 1 doubtful tube, your
pushing it up hill, to find a component fault, so to speak, I`ve just done
a 475 - it had leaky restorer diodes, and 2 defective transistors, which
fortunately weren`t soldered in, buy rather socketed. With determination,
patience, and the humility to ask those who have walked this road before
you, your `scope will be in factory condition sooner than you think. I have
a 547 sitting in storage. Perhaps i`ll start on it soon. What goes wrong
with the 547? The group will tell you.
Good luck, and all patience and determination to you!
Cheers!.....................................................
................................................................Don
Collie ZL4GX

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utm_source=link&utm_campaign=sig-email&utm_content=webmail>
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www.avg.com
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On Fri, Jan 19, 2018 at 1:03 PM, Dave Seiter <d.seiter@...> wrote:

Yeah, sometimes you just have to plug it in and go. Waiting for the
relay
to kick in can seem like it takes forever!
It is a great scope!
-Dave

From: felix_cantor via Groups.Io <felix_cantor=yahoo.com@groups.io>
To: TekScopes@groups.io
Sent: Thursday, January 18, 2018 8:24 AM
Subject: Re: [TekScopes] Help restoring a 547 scope

ok.... ignorance is the mother of all mistakes. It worked!

god! i love this scope.... the trace is so sharp! Amazing.

now i need to fix all the other issues.














Richard Knoppow
 

Regarding Black Beauty caps. There were several series and not all fail the way the infamous ones do with cracking and breaking cases, however, all are paper and _all_ paper caps regardless of maker have had limited lives. Anything old enough to have had BBs in it is old enough to have all its paper caps replaced regardless of make.
   I don't think polyester caps are the best choice and am not sure they are even made. Polypropylene has the best combination of characteristics for most applications. They are not expensive and have far better peformance than the original paper caps had when new. They have excellent RF characteristics and very low storage factor so can be used in timing circuits. They are available from all the usual component dealers.
    A variation on the cleaning routine is what we used at Hewlett-Packard long ago:
1, Remove anything that can be water damaged.
2, Rinse off with warm water from a hose.
3, Wash with a solution of mild liquid dishwashing detergent, like Dawn, in warm water. We sprayed it from a paint sprayer. A brush or brushes can be used to assist the cleaning.
4, Rinse off using warm water from the hose.
5, Blow out as much residual moisture as possible with compressed air (but make sure the blower is of the oil-free type).
6, Bake dry in a ventilated oven, I think we had ours set at about 130F. We baked for a minimum of 48 hours but I liked to go longer.
   Stuff comes out looking new. 130F is low enough not to damage anything but you should still remove plastic parts.
   Now, we had a thermostatically controlled electric oven, most people don't.  I think one can do well with an oven made of a couple of large cardboard boxes with some holes punched to allow circulation and heated with incandescent light bulbs. Most oven thermometers (from the grocery store) go down to 130F so you can stick one into the box from the outside to keep track of the heat.

On 1/18/2018 4:47 PM, donald collie wrote:
Hi Dave,
Sphere Research Corporation have a document available from their website by
Tek, on how to troubleshoot their `scopes - you might like to read it.
Don`t let this `scope beat you, is the correct attitude, and remember :
most faults are simple - you can see or smell them. Are you sure your
`scope is completely dry? I wash my equipment that I import from eBay in a
bath of hot water, and detergent, rinse in hot pure water, and then dry in
front of a fan heater at about 60 degrees celcius, the hottest you can hold
your hand on, for at least 6 hours, preferably overnight. I usually clear
the faults before washing, as washing can provoke faults. Expect multiple
faults in a piece of equipment this age.Your `scope may have the imfamous
"Black Beauty" paper capacitors in it - these go leaky, and are best
replaced. They are recognised by their shiny [now shiny - you`ve cleaned
them!] black plastic cases. These are best replaced by polyester types. You
have a trace! Good! then you have no serious faults. If the `scopes
performance changes with time : Disconnect from the mains, and dry it out
some more. Make a wind tunnel of a cardboard box, and fan heater, so the
whole instrument gets hot, but not too hot. I think you were wise not to
wet the power transformer - I had a transformer fail once after washing.
Next thing i`d ckeck is the various HT`s for correct voltage, using a
meter, and for ripple/noise, using another `scope. This `scope can kill you
, so be careful. If you have a tube checker, I`d then check all the tubes,
because if the PSU`s aren`t 100%, or you have even 1 doubtful tube, your
pushing it up hill, to find a component fault, so to speak, I`ve just done
a 475 - it had leaky restorer diodes, and 2 defective transistors, which
fortunately weren`t soldered in, buy rather socketed. With determination,
patience, and the humility to ask those who have walked this road before
you, your `scope will be in factory condition sooner than you think. I have
a 547 sitting in storage. Perhaps i`ll start on it soon. What goes wrong
with the 547? The group will tell you.
Good luck, and all patience and determination to you!
Cheers!.....................................................................................................................Don
Collie ZL4GX

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On Fri, Jan 19, 2018 at 1:03 PM, Dave Seiter <d.seiter@...> wrote:

Yeah, sometimes you just have to plug it in and go. Waiting for the relay
to kick in can seem like it takes forever!
It is a great scope!
-Dave
--
Richard Knoppow
dickburk@...
WB6KBL

donald collie
 

I use hot, dry, moving air, blowing past all parts of the instrument. I
like the idea of keeping it hot for a full 48 hours, to drive water out of
the cracks. I got impatient once, with a 5245L - when I turned it on the
pilot transformer thet powers the oven, etc, failed.
FWIW........................................................
.................................Don C.
P.S.: I`ve had success with "dual" floor cleaner, but I understand that the
tek note "simple green" was used - this isn`t available where I am, hence
the substitution.

On Fri, Jan 19, 2018 at 2:58 PM, Richard Knoppow <dickburk@...>
wrote:

Regarding Black Beauty caps. There were several series and not all fail
the way the infamous ones do with cracking and breaking cases, however, all
are paper and _all_ paper caps regardless of maker have had limited lives.
Anything old enough to have had BBs in it is old enough to have all its
paper caps replaced regardless of make.
I don't think polyester caps are the best choice and am not sure they
are even made. Polypropylene has the best combination of characteristics
for most applications. They are not expensive and have far better
peformance than the original paper caps had when new. They have excellent
RF characteristics and very low storage factor so can be used in timing
circuits. They are available from all the usual component dealers.
A variation on the cleaning routine is what we used at Hewlett-Packard
long ago:
1, Remove anything that can be water damaged.
2, Rinse off with warm water from a hose.
3, Wash with a solution of mild liquid dishwashing detergent, like Dawn,
in warm water. We sprayed it from a paint sprayer. A brush or brushes can
be used to assist the cleaning.
4, Rinse off using warm water from the hose.
5, Blow out as much residual moisture as possible with compressed air (but
make sure the blower is of the oil-free type).
6, Bake dry in a ventilated oven, I think we had ours set at about 130F.
We baked for a minimum of 48 hours but I liked to go longer.
Stuff comes out looking new. 130F is low enough not to damage anything
but you should still remove plastic parts.
Now, we had a thermostatically controlled electric oven, most people
don't. I think one can do well with an oven made of a couple of large
cardboard boxes with some holes punched to allow circulation and heated
with incandescent light bulbs. Most oven thermometers (from the grocery
store) go down to 130F so you can stick one into the box from the outside
to keep track of the heat.


On 1/18/2018 4:47 PM, donald collie wrote:

Hi Dave,
Sphere Research Corporation have a document available from their website
by
Tek, on how to troubleshoot their `scopes - you might like to read it.
Don`t let this `scope beat you, is the correct attitude, and remember :
most faults are simple - you can see or smell them. Are you sure your
`scope is completely dry? I wash my equipment that I import from eBay in a
bath of hot water, and detergent, rinse in hot pure water, and then dry in
front of a fan heater at about 60 degrees celcius, the hottest you can
hold
your hand on, for at least 6 hours, preferably overnight. I usually clear
the faults before washing, as washing can provoke faults. Expect multiple
faults in a piece of equipment this age.Your `scope may have the imfamous
"Black Beauty" paper capacitors in it - these go leaky, and are best
replaced. They are recognised by their shiny [now shiny - you`ve cleaned
them!] black plastic cases. These are best replaced by polyester types.
You
have a trace! Good! then you have no serious faults. If the `scopes
performance changes with time : Disconnect from the mains, and dry it out
some more. Make a wind tunnel of a cardboard box, and fan heater, so the
whole instrument gets hot, but not too hot. I think you were wise not to
wet the power transformer - I had a transformer fail once after washing.
Next thing i`d ckeck is the various HT`s for correct voltage, using a
meter, and for ripple/noise, using another `scope. This `scope can kill
you
, so be careful. If you have a tube checker, I`d then check all the tubes,
because if the PSU`s aren`t 100%, or you have even 1 doubtful tube, your
pushing it up hill, to find a component fault, so to speak, I`ve just
done
a 475 - it had leaky restorer diodes, and 2 defective transistors, which
fortunately weren`t soldered in, buy rather socketed. With determination,
patience, and the humility to ask those who have walked this road before
you, your `scope will be in factory condition sooner than you think. I
have
a 547 sitting in storage. Perhaps i`ll start on it soon. What goes wrong
with the 547? The group will tell you.
Good luck, and all patience and determination to you!
Cheers!.....................................................
................................................................Don
Collie ZL4GX

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On Fri, Jan 19, 2018 at 1:03 PM, Dave Seiter <d.seiter@...> wrote:

Yeah, sometimes you just have to plug it in and go. Waiting for the relay
to kick in can seem like it takes forever!
It is a great scope!
-Dave

--
Richard Knoppow
dickburk@...
WB6KBL