Maker Pro
Maker Pro

Orange Rocker 30, combo, 2006

N

N_Cook

Jan 1, 1970
0
All valve. Intermitant cutting out.
Incidentally are the solder pads gold plated before soldering ?
No mention of PbF but appearance & paper & indent test hints at PbF. Crimps
adequte, switch functions ok, all solder points look good (for PbF) x5
inspection /tugging, preamp valve bases pass needle test. Other than
resolder most likely suspects , any known problem with these amps?
 
P

Phil Allison

Jan 1, 1970
0
"Nutcase Kook"
All valve. Intermitant cutting out.
Incidentally are the solder pads gold plated before soldering ?
No mention of PbF but appearance & paper & indent test hints at PbF.
Crimps
adequte, switch functions ok, all solder points look good (for PbF) x5
inspection /tugging, preamp valve bases pass needle test. Other than
resolder most likely suspects , any known problem with these amps?


** The control pots on the front are absolute junk - one bump to any knob
and the pot back comes loose and easily result in intermittent sound.



..... Phil
 
N

N_Cook

Jan 1, 1970
0
Definitely PbF, resoldering the usual suspect points.
I realised I was using the wrong gauge of cut down sewing needle and 2 of
the preamp valve socket pins are highly suspect. Those glossy white ceramic
mounts with holes just bigger than the valve pins.
 
A

Arfa Daily

Jan 1, 1970
0
N_Cook said:
Definitely PbF, resoldering the usual suspect points.
I realised I was using the wrong gauge of cut down sewing needle and 2 of
the preamp valve socket pins are highly suspect. Those glossy white
ceramic
mounts with holes just bigger than the valve pins.
If it continues to cut out, a generator, a 'scope and a meter should tell
all. Valve circuits are very simple and very straightforward to trace
signals in, and troubleshoot. Even if it is a bad PbF joint, it should be
easy enough to pin it down to at least a stage, and possibly to a specific
component, based on valve voltages.

Arfa
 
P

Phil Allison

Jan 1, 1970
0
"Arfa Daily"
If it continues to cut out, a generator, a 'scope and a meter should tell
all. Valve circuits are very simple and very straightforward to trace
signals in, and troubleshoot.

** You don't service that many valve guitar amps - do you ??

The ones that were originally well made are now so old they have strange
faults most techs have never seen before - while the ones made more
recently have designed in faults never seen before by anyone.

A few examples.

1. Recent Marshall combo amps with fibreglass PCBs that become LEAKY when
hot - output valve bias goes crazy and even the phase splitter stage goes
way out of DC balance in normal operation because of leakage from anode
tracks to grid tracks. There is simply no fix for this problem.

2. Recent Gibson /Trace Elliot amps that develop mysterious crackling
noises all over the circuit due to the use of water soluble flux that was
never properly washed of the PCB. Removing the main PCB entirely and
washing it thoroughly in solvent is the only fix.

3. Same amps as above use 9 pin PCB mount sockets that SHRINK - yep,
the plastic material used to make the socket shrinks under the heat from
EL84s, reducing the pitch circle diameter so much it is impossible to fit a
new tube in the socket. Replacing all the output valve sockets is the only
fix.

Then there are all the issues with the valves themselves - all new
production now comes from China or the former USSR and most of the valves
have designed in faults of kinds that were never seen previously. Eg.
nearly all 12AX7s now crackle and pop if tapped with the back of a
screwdriver and/or have bad heater cathode hum or are very microphonic -
while octal power types often suffer from bad soldering (PbF ?) on the pins
causing all manner of weird intermittents when the solder joint lets go.

Yep - fixing valve amps is pure joy.


..... Phil
 
N

N_Cook

Jan 1, 1970
0
Arfa Daily said:
If it continues to cut out, a generator, a 'scope and a meter should tell
all. Valve circuits are very simple and very straightforward to trace
signals in, and troubleshoot. Even if it is a bad PbF joint, it should be
easy enough to pin it down to at least a stage, and possibly to a specific
component, based on valve voltages.

Arfa

Coincidence or action of high V on springiness of the socket metal?
One valve base, pin 1 , the other pin 6 , both anodes so killing throughput
if connection fails.

While on valve stuff , has anyone come across any output transformer or
mains transformer ,for that matter, in any equipment , where there is
failure of PbF joint inside the transformer where tail meets magnet wire?
 
A

Arfa Daily

Jan 1, 1970
0
Phil Allison said:
"Arfa Daily"

** You don't service that many valve guitar amps - do you ??



Er, that would be a yes then ... Probably three or four a week, most every
week, and have been doing them for around 40 years ... Whilst some faults
are a little obscure, most are very straightforward, and I'm sure that you
don't have any more trouble fixing them, than I do Phil. I would pick a
fault on a valve amp over a transistor one, every time, as would probably
any engineer who has ever worked with valves. Every stage is pretty much
independent, and troubleshoot-able as a separate entity. You can't say that
about most transistor amps.


The ones that were originally well made are now so old they have strange
faults most techs have never seen before - while the ones made more
recently have designed in faults never seen before by anyone.

A few examples.

1. Recent Marshall combo amps with fibreglass PCBs that become LEAKY
when hot - output valve bias goes crazy and even the phase splitter
stage goes way out of DC balance in normal operation because of leakage
from anode tracks to grid tracks. There is simply no fix for this
problem.


Care to give me a model for that behaviour ? I see a lot of Marshall combos,
as they are built just a few miles from where I live. I have not seen any
similar problems here. I used to visit Jim Marshall in his factory in the
early days. He was a very good friend of a friend of mine. As to the problem
with a - g leakage, I would have thought that you might have been able to
get away with isolating the affected tracks by cutting or even removing them
from the board completely, and then hard wiring.

2. Recent Gibson /Trace Elliot amps that develop mysterious crackling
noises all over the circuit due to the use of water soluble flux that was
never properly washed of the PCB. Removing the main PCB entirely and
washing it thoroughly in solvent is the only fix.

3. Same amps as above use 9 pin PCB mount sockets that SHRINK - yep,
the plastic material used to make the socket shrinks under the heat from
EL84s, reducing the pitch circle diameter so much it is impossible to fit
a new tube in the socket. Replacing all the output valve sockets is the
only fix.

Then there are all the issues with the valves themselves - all new
production now comes from China or the former USSR and most of the valves
have designed in faults of kinds that were never seen previously. Eg.
nearly all 12AX7s now crackle and pop if tapped with the back of a
screwdriver and/or have bad heater cathode hum or are very microphonic -
while octal power types often suffer from bad soldering (PbF ?) on the
pins causing all manner of weird intermittents when the solder joint lets
go.


Whilst I would agree that valve quality is not as good as it was when the
likes of Mullard and Brimar etc made them, I also don't think that they are
quite as bad as you seem to find them, if you buy decent quality ones, or
manufacturer's originals, which have been vetted by the amp manufacturer as
being of the required quality. The Ruby HG (Hi Grade) 12AX7s that I use,
don't crackle and pop, and are no more microphonic than any high gain
triodes have ever been. I also don't find the h - k leakage bad either -
certainly not enough to identify as being a predominant source of unwanted
hum. And as to bad soldering on octal base pins, I honestly can't say that
I've ever seen this problem on any amp that's been across my bench, or on
any replacement valves that I have fitted, which may have had their bases
connected to the leadouts by PbF. Perhaps I've just been lucky ...

Yep - fixing valve amps is pure joy.


.... Phil

Well, I find it so ...

Arfa
 
P

Phil Allison

Jan 1, 1970
0
"Arfa Daily"
"Phil Allison"


Er, that would be a yes then ... Probably three or four a week, most
every week, and have been doing them for around 40 years ... Whilst some
faults are a little obscure, most are very straightforward, and I'm sure
that you don't have any more trouble fixing them, than I do Phil.


** I fix them all - of course.

But there is plenty of trouble with most of them.

I would pick a fault on a valve amp over a transistor one, every time, as
would probably any engineer who has ever worked with valves.


** Solid state gear is far easier to fix and make stay fixed - IM long E.


Care to give me a model for that behaviour ?


** Yep - the JCM2000: TSL100 combo series.

Easy to find many stories about the same problem on usenet and web forums.

I see a lot of Marshall combos, as they are built just a few miles from
where I live. I have not seen any similar problems here. I used to visit
Jim Marshall in his factory in the early days. He was a very good friend
of a friend of mine.

** Nice guy - who never designed or built an amp in his life.

As to the problem with a - g leakage, I would have thought that you might
have been able to get away with isolating the affected tracks by cutting
or even removing them from the board completely, and then hard wiring.

** Tried that idea with the very first example I ever came across.

The PCB wound up looking like a piece of Swiss cheese and still the problem
was not cured.

The only "treatment" that helped at all was to install a fan to keep the
valves and hence PCB cooler.

Colleagues have complained to me about the exact same problem.


Whilst I would agree that valve quality is not as good as it was when the
likes of Mullard and Brimar etc made them, I also don't think that they
are quite as bad as you seem to find them, if you buy decent quality ones,
or manufacturer's originals, which have been vetted by the amp
manufacturer as being of the required quality.


** The BAD valves are already fitted in the amps that come to me for
service.

There are NO " manufacturers originals" available in Australia AFAIK.

The Ruby HG (Hi Grade) 12AX7s that I use, don't crackle and pop, and are
no more microphonic than any high gain triodes have ever been.

** Yaaawwwnnnnnn.....

You compare the particular with the general.

How tedious.

I also don't find the h - k leakage bad either - certainly not enough to
identify as being a predominant source of unwanted hum.

** How odd then that so many new generation valve amps use DC supply for
heaters JUST because of this issue.

And as to bad soldering on octal base pins, I honestly can't say that I've
ever seen this problem on any amp that's been across my bench,


** What planet do you live on ???



..... Phil
 
A

Arfa Daily

Jan 1, 1970
0
Phil Allison said:
"Arfa Daily"


** I fix them all - of course.

But there is plenty of trouble with most of them.




** Solid state gear is far easier to fix and make stay fixed - IM long
E.





** Yep - the JCM2000: TSL100 combo series.

Easy to find many stories about the same problem on usenet and web forums.



** Nice guy - who never designed or built an amp in his life.



** Tried that idea with the very first example I ever came across.

The PCB wound up looking like a piece of Swiss cheese and still the
problem was not cured.

The only "treatment" that helped at all was to install a fan to keep the
valves and hence PCB cooler.

Colleagues have complained to me about the exact same problem.





** The BAD valves are already fitted in the amps that come to me for
service.

There are NO " manufacturers originals" available in Australia AFAIK.



** Yaaawwwnnnnnn.....

You compare the particular with the general.

How tedious.



** How odd then that so many new generation valve amps use DC supply for
heaters JUST because of this issue.




** What planet do you live on ???



.... Phil


Apparently, a very different one from you ...

But then, of course, I was forgetting who I was trying to have a reasoned
discussion with. It had completely slipped my mind that anyone who looks at
anything from a different point of view to you, must be wrong. I suppose
you'll start in on the hysterical abuse hurling next. Well, if that's what
you need to do, go right ahead. I really don't care. And I suppose you know
Jim all the way from upside down land do you ?

Arfa
 
G

Geoffrey S. Mendelson

Jan 1, 1970
0
Arfa said:
Er, that would be a yes then ... Probably three or four a week, most every
week, and have been doing them for around 40 years

If you are such an expert, please tell us how they got that volume
control to go to 11, while (whilst?) everyone knows they only go to 10?

:)

Geoff.
 
A

Arfa Daily

Jan 1, 1970
0
Geoffrey S. Mendelson said:
If you are such an expert, please tell us how they got that volume
control to go to 11, while (whilst?) everyone knows they only go to 10?

:)

Geoff.

If I told you that Geoff, I'd be destroying my niche market. Suffice to say
that they used triodes with more than three electrodes ... d;~}

Arfa
 
P

Phil Allison

Jan 1, 1970
0
"Arfa Daily"
Apparently, a very different one from you ...


** Where reality never intrudes on you rose tinted view.

But then, of course, I was forgetting who I was trying to have a reasoned
discussion with.


** Shame you have not seen or MISSED the common valve amp faults I
mentioned.

Maybe Marshall, Gibson, Fender, Peavey and others ship their bad batches to
Australia deliberately or maybe you have been leading a charmed existence.

It had completely slipped my mind that anyone who looks at anything from a
different point of view to you, must be wrong.


** Now you are completely off with the fairies.

What you have NOT see cannot be dismissed as non existent.

I suppose you'll start in on the hysterical abuse hurling next.


** You are supplying plenty of smug, pommy provocations for that.

Well, if that's what you need to do, go right ahead. I really don't care.

** You don't have a case or a clue - really.

And I suppose you know Jim all the way from upside down land do you ?


** Jim Marshall visited Australia a number of years back, did interviews
with the trade press and gave a presentation to an audience of industry folk
in Sydney.

Before Jim accepted any questions, the MC gave a stern warning to the
assembled audience that Jim was not involved in the design or manufacture of
Marshall amps and that no questions about the notoriously poor design or
appalling reliability of the amps would be allowed.

Wise move.



..... Phil
 
G

Geoffrey S. Mendelson

Jan 1, 1970
0
Arfa said:
If I told you that Geoff, I'd be destroying my niche market. Suffice to say
that they used triodes with more than three electrodes ... d;~}

I figure you could get an extra 20 to 30 quid an amp if you offered to
upgrade them from a maximum of 10 to 11. :)

Geoff.
 
A

Arfa Daily

Jan 1, 1970
0
If I told you that Geoff, I'd be destroying my niche market. Suffice to
say
that they used triodes with more than three electrodes ... d;~}

Let me guess... instead of using thorium as a dopant in the filaments
to enhance electron emission, they used quadmium, right?
[/QUOTE]

How did you know that, huh ? Well that's just great. Now you've told
everyone, and my plans to dominate the music world with one notch upgrades,
are in shreds. Cheers pal ...

Arfa :)
 
A

Arfa Daily

Jan 1, 1970
0
Geoffrey S. Mendelson said:
Don't forget to sell them these:

http://global.aopen.com/products_detail.aspx?Auno=53

Although they have long since been discontinued (or deleted in English).

Geoff.

--


Oh, that's soooo unfair. I was just about to put in an order for some of
those to use as the controller for my LED pilot bulb replacement upgrade ...
Rats. I guess it's back to using the warehouse full of ZX Spectrums that
I've got then ... :-|

Arfa
 
N

N_Cook

Jan 1, 1970
0
Arfa Daily said:
Oh, that's soooo unfair. I was just about to put in an order for some of
those to use as the controller for my LED pilot bulb replacement upgrade ....
Rats. I guess it's back to using the warehouse full of ZX Spectrums that
I've got then ... :-|

Arfa


What is the state of the vacuum-formed plastic of the Sinclair ZX80s these
days?
 
A

Arfa Daily

Jan 1, 1970
0
N_Cook said:
What is the state of the vacuum-formed plastic of the Sinclair ZX80s these
days?

I'd forgotten that ! Dunno. haven't seen one in years ...

Arfa
 
G

Gareth Magennis

Jan 1, 1970
0
** Yep - the JCM2000: TSL100 combo series.

Easy to find many stories about the same problem on usenet and web forums.




Yes, Marshal TSL 100. Sigh. I have had two of these with faulty
PCB's. They do indeed leak, and destroy the output tubes, as the bias
goes totally crazy.
I spent hours on the first one trying to establish what the **** was going
on, as it made no sense whatsoever.


Eventually I phoned Marshall. They know about this problem and are unable
to fix it. You need to replace the PCB with an upgraded design.



Gareth.
 
P

Phil Allison

Jan 1, 1970
0
"Gareth Magennis"
Yes, Marshal TSL 100. Sigh. I have had two of these with faulty
PCB's. They do indeed leak, and destroy the output tubes, as the bias
goes totally crazy.
I spent hours on the first one trying to establish what the **** was going
on, as it made no sense whatsoever.


Eventually I phoned Marshall. They know about this problem and are unable
to fix it. You need to replace the PCB with an upgraded design.


** Hope the are willing to supply that for free ??

Whole PCBs going leaky is hardly an example of "normal wear and tear".



..... Phil
 
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