Toshiba TV29C90 problem; Image fades to black...

Ď "danny burstein" <dannyb@panix.com> Ýăńářĺ óôď ěŢíőěá
news:g0a7pe$mpg$1@reader2.panix.com...
In <g0a7lq0t0c@news5.newsguy.com> phil-news-nospam@ipal.net writes:

In alt.engineering.electrical Tzortzakakis Dimitrios <noone@nospam.void
wrote:

| A shame that Tesla won the infamous "battle" and we don't have DC:-()
But
| then, we would be having a power plant at each neighborhood, instead of
the
| 300 MW ones.

And the latter make easy terrorism targets, too.

And so does that 20 gallons of gasoline parked
in front of your house. And that 500 gallons
of diesel fuel in your basment. And that 20,000
or so gallons in the nearby gas station.

Good that terrorists are brain-washed lunatics, and haven't access to
incendiary rounds:)



--
Tzortzakakis Dimitrios
major in electrical engineering
mechanized infantry reservist
hordad AT otenet DOT gr
--
_____________________________________________________
Knowledge may be power, but communications is the key
dannyb@panix.com
[to foil spammers, my address has been double rot-13 encoded]
 
Ď <phil-news-nospam@ipal.net> Ýăńářĺ óôď ěŢíőěá
news:g0i4ib01ntg@news3.newsguy.com...
In alt.engineering.electrical Tzortzakakis Dimitrios <noone@nospam.void
wrote:

| ? <phil-news-nospam@ipal.net> ?????? ??? ??????
| news:g0f71q111lk@news3.newsguy.com...
|> In alt.engineering.electrical Tzortzakakis Dimitrios
noone@nospam.void
|> wrote:
|
|> | Professional washing machines. One of my very first days 'in the
field'
|> was
|> | to connect some of them. They have a large heating element, you can
|> connect
|> | it single phase, or 3 phase, it just heats up faster (of course) when
|> you
|> | connect it 3 phase. (they have a single phase motor, so it works also
in
|> | pure 230 V).
|
|> If it has 3 elements rated for 230 volts, with 3 separate connections
that
|> would be to three separate phase for a three phase feed, and all
connected
|> to the one phase for a single phase feed, then it should heat up at the
|> same
|> speed, while drawing three times the current (not accounting for the
|> motor).
|
|> I don't know why it should heat up faster in three phase, or why you
would
|> say "of course" about it. I would think it would heat up faster if you
|> took
|> it over to London and hooked it up to a 240 volt supply.
|
| Maybe you connected with single phase just one element? The rest two
| remained unconnected? (3 230 volts elements, connected wye). I'm sure it
| heated up faster, in 3 phase connection.

You were the one who said "it just heats up faster (of course) when you
connect it 3 phase."

I would disagree.

But the fact that you said "(of course)" seems you presume that to be the
general case. Now your most recent comment at least acknowledges that if
not all elements are connected, it won't heat up as fast.

In the simple case, each of 3 elements is individually wired, so you have
a total of 6 leads. When connecting to three phase, one lead of each is
connected to neutral, and each of the other leads is connected to separate
phases. When connecting to single phase, they are all wired in parallel.
Both cases always involve one of the leads from each element connected to
neutral, so those 3 leads can be pre-connected together. So you could
have
just 4 leads. The common neutral lead needs to be rated for all the
current
together for it to be rated properly for single phase.

It should apply the same voltage (230V) to each element, and they should
each
draw the same current. How would you believe this would be slower to
heat?

If the 3 elements were wired _internally_ in star without a neutral lead,
it would still work fine on three phase as long as all elements were equal
impedance. But on single phase, you could only activate 2 of the
elements,
and that would be 2 in series fed with 230 volts. You'd only get 1/6 the
power that way.

Are you assuming the elements would be wired that way? That would clearly
NOT be intended for single phase connection.

The 3 elements could be wired _internally_ in delta. In this case, these
would have to be 400V elements. Connecting 2 leads to 230 volts would
still
give you only 1/6 the power (but more evenly distributed in this case).

So what is the situation that makes _you_ believe that 3 elements
connected
to single phase _will_ draw less power to heat the water than when
connected
to three phase?

I have no idea, we didn't even open up the washing machines as they were
under guarantee. I know that the landlady's electrician connected the wms
single phase, and I connected (in the distr.box) all 3 phases. I suppose it
has 3 elements connected wye, and single phase is 1 element, plus motor and
automation.



--
Tzortzakakis Dimitrios
major in electrical engineering
mechanized infantry reservist
hordad AT otenet DOT gr
 
? "James Sweet" <jamessweet1@trashmail.net> ?????? ??? ??????
news:HKnVj.128$6D1.49@trndny02...
The central air kicks on without my lights dimming, and I am in North
Central Florica.


Mine dim slightly for an instant when my 3 ton heat pump kicks in, it's
only noticeable with the few incandescent lights left in the house though.
The LRA on that thing is something like 90A. I think most of the drop must
be in the 50' or so of 2/0 AL wire between the meter base and the
transformer though as they don't seem to dim at all from any of the
neighbors.
That's because you have no bloody wind-turbines on your grid. We have here,
and I had to include them in my thesis, and these things seriously harm the
voltage quality in interconnected grids. In stand-alone residence
installations, they work ok, probably with photovoltaics, but here they are
a disaster, in whole Crete all the lights flicker every evening when the
bloody wing stalls them and they convert momentarily from generating to
motors. I prefer old-fashioned fossil-fuel fired power plants, after all
smoking chimneys is a token of peace:)



--
Tzortzakakis Dimitrios
major in electrical engineering
mechanized infantry reservist
hordad AT otenet DOT gr
 
Seems to me that you have a problem with anything made in China.
We all know that you get some crap made there but sometimes
some good stuff comes from there.
There is a difference between items made in China and designed in China. I
have plenty of Chinese-manufactured items that are of high quality. I have
many fewer that were _designed_ there. One is an iRiver H120 jukebox, which
is of very high quality.
 
"Sam Goldwasser" <sam@plus.seas.upenn.edu> wrote in message
news:6w63smarx0.fsf@plus.seas.upenn.edu...
I have been a member in good standing with eBay since 1999. As readers
of Sam's Laser FAQ are probably aware, I have acquired a large number of
lasers and related items on eBay, most at bargain basement prices. All in
all I have been very satisfied with the eBay experience. Until now.

For a blow-by-blow saga of what I'm experiencing now, please go to

http://repairfaq.cis.upenn.edu/Misc/ebayhorror1.htm

I will be updating this as it plays out. I expect the outcome to be
satisfactory, but the route it's taking is like one of those nightmares
where you're trapped on a 15 dimensional mobius strip. :)

Comments welcome!

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above
is
ignored unless my full name AND either lasers or electronics is included
in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
Interesting. I was in the middle of a (small) transaction with a longtime
reputable seller whose account was then suspended the same day as yours.
Maybe a hacker has figured out how to fool their screening program to create
havoc. For example, If he creates an account using your address, then is
suspended for behaving badly, his account would be linked to yours because
of the same address.

--
Adam Norton

(Remove antispam feature before replying)
 
Sam Goldwasser writes:

Comments welcome!
I'm sorry to hear you're having these problems. I assumed you had some
tale of a fraudster victimizing you, but apparently your problem is
eBay's fraud detection false-positive'izing you.

All I can say is the eBay as an service and as a corporation has been
degrading significantly for years. It started with things like
"protecting" us by censoring email addresses, and then things like
hiding bidder IDs, and now the recent feedback changes. Bah.

It's really sad. Technology seems to be marching backwards in a lot of
ways. Aside from portability, our grandparents had better telephones
than these portable things we carry around today. It used to cost money
to talk on the phone or send mail, so incoming phone calls or email were
generally worthy of your attention. Now I spend significant time daily
attending to worthless phone calls and spam, coming from instrusive
idiots who have no possibility of profiting from their nuisance. Cheap
communication not only explodes into time-wasting frivolity, it empowers
the foolish to "get in touch" with you personally. When it cost money
to talk, the foolish didn't have any to waste.

I actually feel better about being bum-rushed by panhandlers on the
streets these days. At least they're limited by space, time, and my
appearance in a public place, limitations that don't apply to electronic
gooks, and one gets at least a little human interaction of a lukewarm
sort.

The "fall" of the Internet from the crime-free 1970s-1980s to present
day just confirms the doctrine of original sin.

If Ben Franklin has proposed a postal system where 98 percent of the
traffic was spam and frauds, he'd be laughed out of town.
 
Sam Goldwasser <sam@plus.seas.upenn.edu> wrote in message
news:6w8wxhyk70.fsf@plus.seas.upenn.edu...
"anorton" <anorton@removethis.ix.netcom.com> writes:

"Sam Goldwasser" <sam@plus.seas.upenn.edu> wrote in message
news:6w63smarx0.fsf@plus.seas.upenn.edu...
I have been a member in good standing with eBay since 1999. As readers
of Sam's Laser FAQ are probably aware, I have acquired a large number
of
lasers and related items on eBay, most at bargain basement prices.
All in
all I have been very satisfied with the eBay experience. Until now.

For a blow-by-blow saga of what I'm experiencing now, please go to

http://repairfaq.cis.upenn.edu/Misc/ebayhorror1.htm

I will be updating this as it plays out. I expect the outcome to be
satisfactory, but the route it's taking is like one of those
nightmares
where you're trapped on a 15 dimensional mobius strip. :)

Comments welcome!

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/

Interesting. I was in the middle of a (small) transaction with a
longtime
reputable seller whose account was then suspended the same day as yours.
Maybe a hacker has figured out how to fool their screening program to
create
havoc. For example, If he creates an account using your address, then
is
suspended for behaving badly, his account would be linked to yours
because
of the same address.

That's sort of along the lines of what I'm thinking as well. Assuming it
isn't
a typo on someone's part entering eBay IDs, then I'm sure there is
something legitimate to the investigation. But some elementary
Web and directory searches would quickly reveal who has the real
addresses and other contact information. This is like a bad Hitchcock
script!

Thanks.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above
is
ignored unless my full name AND either lasers or electronics is included
in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
and havoc at Paypal
http://blog.statcounter.com/?p=74

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
Sam Goldwasser <sam@plus.seas.upenn.edu> wrote in message
news:6w8wxhyk70.fsf@plus.seas.upenn.edu...
"anorton" <anorton@removethis.ix.netcom.com> writes:

"Sam Goldwasser" <sam@plus.seas.upenn.edu> wrote in message
news:6w63smarx0.fsf@plus.seas.upenn.edu...
I have been a member in good standing with eBay since 1999. As readers
of Sam's Laser FAQ are probably aware, I have acquired a large number
of
lasers and related items on eBay, most at bargain basement prices.
All in
all I have been very satisfied with the eBay experience. Until now.

For a blow-by-blow saga of what I'm experiencing now, please go to

http://repairfaq.cis.upenn.edu/Misc/ebayhorror1.htm

I will be updating this as it plays out. I expect the outcome to be
satisfactory, but the route it's taking is like one of those
nightmares
where you're trapped on a 15 dimensional mobius strip. :)

Comments welcome!

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/

Interesting. I was in the middle of a (small) transaction with a
longtime
reputable seller whose account was then suspended the same day as yours.
Maybe a hacker has figured out how to fool their screening program to
create
havoc. For example, If he creates an account using your address, then
is
suspended for behaving badly, his account would be linked to yours
because
of the same address.

That's sort of along the lines of what I'm thinking as well. Assuming it
isn't
a typo on someone's part entering eBay IDs, then I'm sure there is
something legitimate to the investigation. But some elementary
Web and directory searches would quickly reveal who has the real
addresses and other contact information. This is like a bad Hitchcock
script!

Thanks.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above
is
ignored unless my full name AND either lasers or electronics is included
in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
and havoc at Paypal
http://blog.statcounter.com/?p=74

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
"Juan" <juandelnorte@gmail.com> wrote in message
news:1538bd27-b3eb-41e2-a115-093b0ea63712@l28g2000prd.googlegroups.com...
My HP LaserJet 4 all of a sudden started printing black over the whole
page. Beneath the black I can see that the image I'm printing is
transferred onto the page, but it is mostly obscured by the toner
stuck onto the page all over.

My (very limited) understanding is that this may be caused when the
corona wire doesn't properly charge the drum. Is this correct? Is it
something else?

Is this problem caused by a broken corona wire? Is the corona wire
part of the toner cartridge, and if so, will replacing the toner
cartridge fix the problem? Is there someplace else to look for a
broken or disconnected wire? Is there a possible fault in the circuit
that applies a charge to the corona wire?

This LaserJet 4 has been a faithful and reliable workhorse for about
15 years. I'd like to find the problem and fix it, if possible.

Can anyone give me some insights as to what might be the cause and
solution for this problem?

Thanks,
Juan
Have a look here:-
http://www.fixyourownprinter.com/search/forums?q=LJ4

Colin
 
"Juan" <juandelnorte@gmail.com> wrote in message
news:1538bd27-b3eb-41e2-a115-093b0ea63712@l28g2000prd.googlegroups.com...
My HP LaserJet 4 all of a sudden started printing black over the whole
page. Beneath the black I can see that the image I'm printing is
transferred onto the page, but it is mostly obscured by the toner
stuck onto the page all over.

My (very limited) understanding is that this may be caused when the
corona wire doesn't properly charge the drum. Is this correct? Is it
something else?

Is this problem caused by a broken corona wire? Is the corona wire
part of the toner cartridge, and if so, will replacing the toner
cartridge fix the problem? Is there someplace else to look for a
broken or disconnected wire? Is there a possible fault in the circuit
that applies a charge to the corona wire?

This LaserJet 4 has been a faithful and reliable workhorse for about
15 years. I'd like to find the problem and fix it, if possible.

Can anyone give me some insights as to what might be the cause and
solution for this problem?

Thanks,
Juan
Have a look here:-
http://www.fixyourownprinter.com/search/forums?q=LJ4

Colin
 
I have a 4M that's over 15 years old; I hope it keeps working forever.
Wonderful product.

I had a similar problem several months ago with the sudden apparance of wide
horizontal black stripes across the page. You could see the text or graphics
"behind" them.

I assumed there was something wrong with the printer itself. * After some
slightly acrimonious arguing with an expert on the HP user site, I schlepped
the printer to a printer service shop who was kind enough to make a test
print with their cartridge.

No problems. There was nothing wrong with the printer.

I bought a new HP cartridge, and it's worked fine since.

I'm have a lot of experience service electronic equipment, but the 4M is not
a product I'd like to rip into. I'd recommend finding someone with a spare
cartridge to confirm just where the problem lies.

If it turns out the printer needs repair, you find it much less expensive
to buy a used, (supposedly) reconditioned one. They're all over the Web, for
cheap.

* Part of the reason was my assumption that the laser discharged the "white"
areas on the drum. Actually, it discharges the "black" parts of the image.
 
I have a 4M that's over 15 years old; I hope it keeps working forever.
Wonderful product.

I had a similar problem several months ago with the sudden apparance of wide
horizontal black stripes across the page. You could see the text or graphics
"behind" them.

I assumed there was something wrong with the printer itself. * After some
slightly acrimonious arguing with an expert on the HP user site, I schlepped
the printer to a printer service shop who was kind enough to make a test
print with their cartridge.

No problems. There was nothing wrong with the printer.

I bought a new HP cartridge, and it's worked fine since.

I'm have a lot of experience service electronic equipment, but the 4M is not
a product I'd like to rip into. I'd recommend finding someone with a spare
cartridge to confirm just where the problem lies.

If it turns out the printer needs repair, you find it much less expensive
to buy a used, (supposedly) reconditioned one. They're all over the Web, for
cheap.

* Part of the reason was my assumption that the laser discharged the "white"
areas on the drum. Actually, it discharges the "black" parts of the image.
 
"Sam Goldwasser" <sam@plus.seas.upenn.edu> wrote in message
news:6w3anpyjsr.fsf@plus.seas.upenn.edu...
Don Bowey <dbowey@comcast.net> writes:

On 6/6/08 7:40 PM, in article 6w63smarx0.fsf@plus.seas.upenn.edu, "Sam
Goldwasser" <sam@plus.seas.upenn.edu> wrote:

I have been a member in good standing with eBay since 1999. As readers
of Sam's Laser FAQ are probably aware, I have acquired a large number
of
lasers and related items on eBay, most at bargain basement prices. All
in
all I have been very satisfied with the eBay experience. Until now.

For a blow-by-blow saga of what I'm experiencing now, please go to

http://repairfaq.cis.upenn.edu/Misc/ebayhorror1.htm

I will be updating this as it plays out. I expect the outcome to be
satisfactory, but the route it's taking is like one of those nightmares
where you're trapped on a 15 dimensional mobius strip. :)

Comments welcome!

I've not had a problem of that kind with the idiots, but I have attempted
to
do a problem resolution with them and find them useless droids.

To minimize contact with them I even quit using Paypal, as they wanted
too
much personal information such as checking account, etc. I don't trust
them
and never will.

Were I you, I'd talk with my attorney about the bad experience.

Good luck; you'll need it.;

For me, I do eBay for fun. It's not like a day job so being kicked off
for a few days may be a good thing. Other than the time I've spent
trying to communicate with the droids and writing up the saga, it gives
me more time for other things. Perhaps they will have done me a favor
if I never get back on! :)

But I could just imagine if this happened to someone whose business
was selling on eBay.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above
is
ignored unless my full name AND either lasers or electronics is included
in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

Very possibly a phishing e-mail. Any time you get a suspicious e-mail from
"Ebay" you should NOT respond to any link in the suspect e-mail. Go directly
to Ebay's security center and give them the details, including the source
code of the suspect e-mail.

Since you clicked on the link contained in the e-mail it is important you do
virus and malware scans IMMEDIATELY.


Mark Z.
 
"Sam Goldwasser" <sam@plus.seas.upenn.edu> wrote in message
news:6w3anpyjsr.fsf@plus.seas.upenn.edu...
Don Bowey <dbowey@comcast.net> writes:

On 6/6/08 7:40 PM, in article 6w63smarx0.fsf@plus.seas.upenn.edu, "Sam
Goldwasser" <sam@plus.seas.upenn.edu> wrote:

I have been a member in good standing with eBay since 1999. As readers
of Sam's Laser FAQ are probably aware, I have acquired a large number
of
lasers and related items on eBay, most at bargain basement prices. All
in
all I have been very satisfied with the eBay experience. Until now.

For a blow-by-blow saga of what I'm experiencing now, please go to

http://repairfaq.cis.upenn.edu/Misc/ebayhorror1.htm

I will be updating this as it plays out. I expect the outcome to be
satisfactory, but the route it's taking is like one of those nightmares
where you're trapped on a 15 dimensional mobius strip. :)

Comments welcome!

I've not had a problem of that kind with the idiots, but I have attempted
to
do a problem resolution with them and find them useless droids.

To minimize contact with them I even quit using Paypal, as they wanted
too
much personal information such as checking account, etc. I don't trust
them
and never will.

Were I you, I'd talk with my attorney about the bad experience.

Good luck; you'll need it.;

For me, I do eBay for fun. It's not like a day job so being kicked off
for a few days may be a good thing. Other than the time I've spent
trying to communicate with the droids and writing up the saga, it gives
me more time for other things. Perhaps they will have done me a favor
if I never get back on! :)

But I could just imagine if this happened to someone whose business
was selling on eBay.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above
is
ignored unless my full name AND either lasers or electronics is included
in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

Very possibly a phishing e-mail. Any time you get a suspicious e-mail from
"Ebay" you should NOT respond to any link in the suspect e-mail. Go directly
to Ebay's security center and give them the details, including the source
code of the suspect e-mail.

Since you clicked on the link contained in the e-mail it is important you do
virus and malware scans IMMEDIATELY.


Mark Z.
 
"James Sweet" <jamessweet1@trashmail.net> wrote in message
news:wlq2k.697$kW2.156@trnddc01...
William Sommerwerck wrote:

There is a difference between items made in China and designed in
China. I have plenty of Chinese-manufactured items that are of high
quality. I have many fewer that were _designed_ there. One is an
iRiver H120 jukebox, which is of very high quality.

Isn't iRiver Korean? We did some work with their products a while back,
had a couple of their engineers over here, I'm pretty sure they weren't
Chinese but I could be wrong.
Good point. I don't remember seeing any "country of design" on the
literature. I just "assumed" it was a wholly Chinese product.

If it's a Korean design, that would explain a lot of things.

I'm hoping Toshiba will come out with a direct-replacement 100GB (or larger)
vertical-recording hard drive. But I'm not holding my breath.

By the way, there's an "open" group called RockBox that makes improved
operating systems for many jukeboxes, including iRiver models.
 
"James Sweet" <jamessweet1@trashmail.net> wrote in message
news:wlq2k.697$kW2.156@trnddc01...
William Sommerwerck wrote:

There is a difference between items made in China and designed in
China. I have plenty of Chinese-manufactured items that are of high
quality. I have many fewer that were _designed_ there. One is an
iRiver H120 jukebox, which is of very high quality.

Isn't iRiver Korean? We did some work with their products a while back,
had a couple of their engineers over here, I'm pretty sure they weren't
Chinese but I could be wrong.
Good point. I don't remember seeing any "country of design" on the
literature. I just "assumed" it was a wholly Chinese product.

If it's a Korean design, that would explain a lot of things.

I'm hoping Toshiba will come out with a direct-replacement 100GB (or larger)
vertical-recording hard drive. But I'm not holding my breath.

By the way, there's an "open" group called RockBox that makes improved
operating systems for many jukeboxes, including iRiver models.
 
daviddschool <daviddschool@gmail.com> wrote in message
news:8b623048-0088-48c6-ac21-865fc4f76bcd@34g2000hsf.googlegroups.com...
I am looking for a non-soldering way of attaching flexible wire to a
LED leg - I know I could wrap it, but I think it time it might come
loose or the connection might not be the greatest - has anyone come
out with a product that will work so if I wanted to change the LED, it
would be easy to attach the new one without soldering it?

Thanks in advance,
Chop down a DIL socket to just 2 pins and solder to the socket pins

--
General electronic repairs, most things repaired, other than TVs and PCs
http://www.divdev.fsnet.co.uk/repairs.htm

Diverse Devices, Southampton, England
 
"Jim Adney" <jadney@vwtype3.org> wrote in message
news:gn3l4451sodc8qv99usi3ohpsrmtqrahms@4ax.com...
I recently got out my trusty Heathkit TT-1 tube tester to check a
bunch of tubes that had accumulated here. I've stopped using its roll
chart, because it's starting to show its age, and I assume the roll
chart is not replacable. If it IS, I'd love to hear about it.


this does bring up an interesting thought, not totally unrelated - with
today's inexpensive computer interfaces, why not build/market a tube tester
accessory that would plug into a USB bus - all you would need is one of each
kind of socket on the unit, and a couple of power sources (filament and
plate/bias voltages) - so a set of SCRs to choose filament voltage and apply
it to the proper pins, 4 or four cheap D/As to create the voltages (maybe
with an HV op amp to create higher voltages), and op amps and A/D with a mux
to scan voltages and currents on all the pins of every socket - this would
probably take no more than 50 to 100 parts and a small PC board and you
could have the tube info read from a computer database and have the test
results displayed graphically - transconductance plots, leakage, emissivity,
all those esoteric parameters.

Done as a labor of love, where the NRE is not amortized, it could be
profitable at the $150 to $300 price range - wouldn't this be a good thing?
it would take less space, be more accurate, faster and less error prone than
using a 40 to 60 year old largely mechanical device.


so, who's gonna make it?


** Posted from http://www.teranews.com **
 
Andy Cuffe writes:

The new feedback system now makes feedback for buyers meaningless.
They should just make it so sellers can't leave feedback at all since
a buyer's feedback no longer tells you anything.
It's like the Model T or the 500 phone set, which came in any color you
wanted, as long as that color was black.

You can leave any kind of eBay feedback you like for buyers, as long as it
is positive.
 
"Ron(UK)" <ron@lunevalleyaudio.com> wrote in message
news:UsCdnTrXO82nZ9rVnZ2dnUVZ8j6dnZ2d@bt.com...
As the subject says, I have a Denon PMA 250 with an open circuit mains
transformer primary - no doubt the thermal protection has failed. Can
anyone tell me the secondary voltage?
**I only have a manual for a PMA350-II. It is rated at 50 W/ch. Secondary
Voltage is rated 34-0-34. I reckon 30-0-30 sounds about right for your amp.
I had the same problem with a Denon a couple of months back. Bloody potted
toroidals!


--
Trevor Wilson
www.rageaudio.com.au
 

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