Digest for sci.electronics.repair@googlegroups.com - 12 updates in 2 topics

9:41 AM Penedão 0 comments
Martin James Smith <marty889@freeserve.net>: Jul 30 07:36PM +0100

Hi all,
 
Say I wanted to buy the most reliable new compact car on the market
right now, the one least likely to ever break down on me in the
future, what would it be?
 
cheers,
 
MS
Fox's Mercantile <jdangus@att.net>: Jul 30 01:41PM -0500

On 7/30/20 1:36 PM, Martin James Smith wrote:
> future, what would it be?
 
> cheers,
 
> MS
 
A 1965 Chevrolet 1/2 ton 6' bed pickup truck.
 
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 30 12:11PM -0700

But only one from inland Texas.
 
Peter Wieck
Melrose Park, PA
"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 30 12:18PM -0700

How high is "UP"?
 
About any vehicle above a minimum standard will last, effectively forever with proper maintenance and appropriate driving techniques.
 
As you are specifying current production by implication, and are not focused just on cost, I suggest you start with the Toyota Prius family, then look at various of the Hyundai family.
 
All of which get good reports, and Hyundai has its very long warranty.
 
Then, there is the entire Subaru family - if AWD is an attractant.
 
With proper care-and-feeding, you should get a reliable 200,000 miles (322,000 km) out of any of them.
 
Peter Wieck
Melrose Park, PA
Mike Coon <gravity@mjcoon.plus.com>: Jul 30 09:26PM +0100

In article <trmdnexyENfKib7CnZ2dnUU7-WHNnZ2d@giganews.com>,
jdangus@att.net says...
 
> > cheers,
 
> > MS
 
> A 1965 Chevrolet 1/2 ton 6' bed pickup truck.
 
I think that could only be made "compact" by a crusher!
 
Mike.
Jon Elson <elson@pico-systems.com>: Jul 30 04:17PM -0500

Martin James Smith wrote:
 
 
> Say I wanted to buy the most reliable new compact car on the market
> right now, the one least likely to ever break down on me in the
> future, what would it be?
 
I've had fantastic luck with Toyota and Honda. I am driving a Honda Civic
hybrid now with over 160K miles on it. Other than standard maintenance, the
only thing needing service was the hybrid battery, covered under
manufacturer's warranty.
 
We are still running our 2000 Toyota Sienna van with 250K miles. The
plastic door handles are crumbling, and new old stock replacement handles
can be had, but they are also deteriorated, so there's no point in it.
The only service on that one, other than normal stuff (tires, brakes,
battery) is a radiator that I can chalk up to a deer collision years before.
 
Before that, I had a Toyota Corolla stick shift station wagon that I kept
for 19 years! I got at least 160K miles out of that one, and it was still
running after 2 accidents, when we decided to retire it.
 
Jon
Jon Elson <elson@pico-systems.com>: Jul 30 04:24PM -0500


> How high is "UP"?
 
> About any vehicle above a minimum standard will last, effectively forever
> with proper maintenance and appropriate driving techniques.
 
Well, we had several "US label" cars that needed a lot of work, both under
warranty and after warranty expiration. Stuff like engine block water
leaks, AC constantly leaking refrigerant, $3000 transmission overhauls, and
on and on, even before reaching 100K miles.
 
Our Toyota and Honda vehicles have run well over 100K with almost no repairs
other than tires, brakes, batteries, windshield wipers and such.
 
Our 2000 Toyota van with 250K miles has had a new starter and recently a new
radiator, but I think that was due to a deer collision.
 
My 1989 Toyota Corolla wagon ran 160K miles with only a starter at 136K, but
was finally retired after 2 collisions.
 
My current driver is a Honda Civic hybrid with 160K miles, still running
like new. ZERO maintenance outside the scheduled stuff, except when the
damn mice chewed the wires under the hood. That's 11+ years old.
 
Jon
John Robertson <spam@flippers.com>: Jul 30 03:39PM -0700

> But only one from inland Texas.
 
> Peter Wieck
> Melrose Park, PA
 
They don't salt the roads in the winter there?
 
John ;-#)#
Ralph Mowery <rmowery28146@earthlink.net>: Jul 30 06:42PM -0400

In article <-76dna8eHf8cp77CnZ2dnUU7-SXNnZ2d@giganews.com>, elson@pico-
systems.com says...
> warranty and after warranty expiration. Stuff like engine block water
> leaks, AC constantly leaking refrigerant, $3000 transmission overhauls, and
> on and on, even before reaching 100K miles.
 
Some vehicles have known major problems. Like my son had a Nissan
Rouge. The transmission went out at around 135,000 miles and cost him
$ 4000 to replace. Turns out that transmission was known to go bad in
many of them and the company had extended the warrenty to 120,000 miles.
That did not help my son.
 
I have only bought Toyotas for the last 30 years. Other than normal
wear items like brakes and tires and batteries and scheduled maintence
my 1991 needed a $ 500 sensor at 130,000 miles. Sold it off at slightly
over 190,000 miles with no other problems.
 
I would never buy anything but a Toyota or Honda unless I needed a full
size truck or some other thing they did not make.
I have had reports that KIA is also good,but not sure.
John Robertson <spam@flippers.com>: Jul 30 03:42PM -0700

On 2020/07/30 2:24 p.m., Jon Elson wrote:
> warranty and after warranty expiration. Stuff like engine block water
> leaks, AC constantly leaking refrigerant, $3000 transmission overhauls, and
> on and on, even before reaching 100K miles.
 
My 1994 Mercury Villager soccer-mom/dad van has almost 300K kms on the
odometer, no major engine work that I know of, but I bought it used
about ten years ago....
 
Mind you one of the engine mounts has split.
 
John :-#)#
Mike S <mscir@yahoo.com>: Jul 31 02:53AM -0700

On 7/30/2020 11:41 AM, Fox's Mercantile wrote:
 
>> cheers,
 
>> MS
 
> A 1965 Chevrolet 1/2 ton 6' bed pickup truck.
 
I've owned a Toyota pickup truck (18R engine), Corolla, Celica, an 89
Acura Integra, and I'm driving a 2001 Civic Ex. I thought they were all
great: reliable, low smog, good power and mileage, decent handling, low
maintenance, no surprises or egregious design flaws, and I could do most
of the work on them myself. I guess I would say Honda or Acura, and then
Toyota coming in a very close second.
Martin James Smith <marty889@freeserve.net>: Jul 30 07:38PM +0100

Soz, wrong group!
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Digest for sci.electronics.repair@googlegroups.com - 2 updates in 1 topic

9:40 AM Penedão 0 comments
Jeff Urban <jurb6006@gmail.com>: Jul 30 12:04AM -0700

I am aware of that. If they use a single triode for a splitter the cathode voltage should be what, a third ? In a hifi amp, if they got a full blown Williamson and I mean with the cathode taps they are going to need a hell of alot of voltage on it. I am not sure the old ECC83 an do it. Most full Williamsons with the cathode taps have another stage, sometimes with a bootstrap to get the drive they need. But that type of amp is rare. Mac made one or two, my Uncle built a pair of monoblocks using Chicago BO-15 transformers. The BO-14s do not have cathode taps. Those were actually popular transformers back then, but the BO-15 was really hard to get.
 
Tubes, I tell you what, those amps my Uncle built sounded better than any tube amps I ever heard till then or since.
Phil Allison <pallison49@gmail.com>: Jul 30 02:04AM -0700

Jeff Urban wrote:
 
==================
 
 
> I am aware of that. If they use a single triode for a splitter the cathode voltage should be what, a third ? In a hifi amp, if they got a full blown Williamson and I mean with the cathode taps they are going to need a hell of alot of voltage on it. I am not sure the old ECC83 an do it. Most full Williamsons with the cathode taps have another stage, sometimes with a bootstrap to get the drive they need. But that type of amp is rare.
 
** I have rarely seen a total red herring chased down a rabbit hole so thoroughly before.
 
Quite something.
 
...... Phil
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Digest for sci.electronics.repair@googlegroups.com - 2 updates in 1 topic

9:40 AM Penedão 0 comments
John-Del <ohger1s@gmail.com>: Jul 28 01:26PM -0700

On Tuesday, July 28, 2020 at 7:44:42 AM UTC-4, Jeff Urban wrote:
 
> You never know what kind of drugs these engineers are on.
 
> I remember an RCA TV like a CTC211 or something, projection. They had a string of like seven transistors just to turn on the convergence subsystem. Why ? And it wasn't like there were a bunch of protection lines going to it, just a voltage and that's it. It was also not in the feedback loop.
 
> I think they just want shit to be as hard to fix as possible.
 
 
 
I think it's time to go back to A batteries..
Phil Allison <pallison49@gmail.com>: Jul 28 08:07PM -0700

Jeff Urban wrote:
 
=========================
> If the cathode is positive I can see why to put DC slightly higher on the filament. It will prevent any conduction I would think. However +70 is up there. What cathodes are at that high a positive voltage ?
 
 
** Marshalls all have cathode follower in the pre-amp where the the cathode is about 140V above ground.
 
 
 
> I guess maybe for a common plate stage. (cathode follower) Perhaps a triode single phase splitter to drive push pull output tubes.
 
 
** Yep - about 90V above ground there too.
 
 

> As far as getting rid of hum, you have to rectify that 70 volts,
 
 
** Derived from the HT so just two Rs and one small C.
 
DC heater volts are used on many guitar amps and some hi-fi ones as well.
 
 
 
.... Phil
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Digest for sci.electronics.repair@googlegroups.com - 8 updates in 3 topics

9:40 AM Penedão 0 comments
Phil Allison <pallison49@gmail.com>: Jul 27 06:51PM -0700

Hi,
 
positive DC biasing the heater winding of a tube amp is occasionally used to eliminate H-K hum in the pre-amp - a clever alternative to using a well filtered DC supply for the same job as done in many guitar amps.
 
However, it means the heater circuit is no longer firmly grounded and could acquire a high voltage under certain fault conditions.
 
Marshall in their infinitesimal wisdom have done this on their latest models
- the JVM 400 series. The 6.3V heater winding is floated to about +70V DC using a voltage divider off the HT.
 
Now, output tubes like the EL34s used are prone to failures that send their cathode to a high voltage or short pin 3 to pin 2 ( anode to heater arc over). When that happens, the heater winding rises to meet the B+ supply. None of the other tubes will like that - max rated H-K voltage is about 100V.
 
Maybe the idea is *too* clever.
 
 
.... Phil
Jeff Urban <jurb6006@gmail.com>: Jul 28 04:44AM -0700

If the cathode is positive I can see why to put DC slightly higher on the filament. It will prevent any conduction I would think. However +70 is up there. What cathodes are at that high a positive voltage ? All you need is an equal or slightly higher positive voltage.
 
I guess maybe for a common plate stage. (cathode follower) Perhaps a triode single phase splitter to drive push pull output tubes.
 
As far as getting rid of hum, you have to rectify that 70 volts, so why not just rectify the damn filament voltage in the first place ?
 
You never know what kind of drugs these engineers are on.
 
I remember an RCA TV like a CTC211 or something, projection. They had a string of like seven transistors just to turn on the convergence subsystem. Why ? And it wasn't like there were a bunch of protection lines going to it, just a voltage and that's it. It was also not in the feedback loop.
 
I think they just want shit to be as hard to fix as possible.
bruce2bowser@gmail.com: Jul 27 10:00AM -0700

What is this type of screen called? Where can you get it from?
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 27 01:43PM -0400

> What is this type of screen called? Where can you get it from?
 
McMaster-Carr, if you're prepared to paint it yourself. Very roughly
$10 per square foot in aluminum, $20 in brass.
 
Cheers
 
Phil Hobbs
 
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
 
http://electrooptical.net
http://hobbs-eo.com
whit3rd <whit3rd@gmail.com>: Jul 27 11:34PM -0700

> What is this type of screen called? Where can you get it from?
 
Sometimes called 'shadow mask' and there's some behind the glass in
every color CRT.
Jeff Urban <jurb6006@gmail.com>: Jul 28 04:29AM -0700

>Sometimes called 'shadow mask' and there's some behind the glass in
>every color CRT.
 
Only the older ones, the inline gun ones had an aperture grill which is only vertical. Slits not holes.
John-Del <ohger1s@gmail.com>: Jul 27 02:01PM -0700

Came in "dead", but only had really really bad tape monitor/source switch contacts. Cleaned all controls and switches and runs fine, except the FM seems to have weak sensitivity. AM seems OK. Might be normal but I'd like to eyeball the FM section anyway.
dplatt@coop.radagast.org (Dave Platt): Jul 27 05:55PM -0700

>switch contacts. Cleaned all controls and switches and runs fine,
>except the FM seems to have weak sensitivity. AM seems OK. Might be
>normal but I'd like to eyeball the FM section anyway.
 
One net article suggests that the 7951 is a cosmetic (black) variation
of the 795.
 
HiFiEngine.com doesn't have pages for the AH795/AH7951, but has a page
for the AH794, and the service-manual for that model implies that it
might apply to the 90, 92, 95, and 99 models as well. Philips seems to
have produced families of receivers which varied cosmetically and in
their audio power outputs, but it seems plausible that the basic
schematic may be the same (or at least quite similar) across the
family.
 
So, go register at HiFiEngine.com (it's free, and I've not gotten any
spam or other nonsense from them after registering years ago) and
download the AH794 service manual. I'd guess it'll be close enough to
let you debug the FM section.
 
If it is, I don't think you should expect miracles. If I'm reading the
schematic for U1001 (the FM tuner board) rightly... well, it appears
to have _one_ varactor-tuned RF amplifier transistor (a BF324 run
common-base) and the varactor-tuned local oscillator, feeding a
one-transistor BF494 mixer/amp, which then feeds a 10.7 MHz crystal
filter, a BF494 IF amplifier, and another crystal filter. There's
more IF gain in the TBA570A AM/FM chip. There's a double-tuned
transformer in front of all of this, which probably gives it some
selectivity against out-of-band signals, but that's it.
 
So, its selectivity isn't going to be wonderful. Sensitivity might be
something you can address, perhaps... RF and IF alignment, maybe
changing out those BF324/BF494 transistors with something a bit less
Neolithic :-)
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Digest for sci.electronics.repair@googlegroups.com - 1 update in 1 topic

9:40 AM Penedão 0 comments
John Robertson <spam@flippers.com>: Jul 26 05:55PM -0700

On 2020/07/26 2:17 a.m., Adrian Tuddenham wrote:
 
>>> Nice. Did you ever consider building a lexan box to mount it in?
 
>> No, my family are careful around it and we no longer have a cat...
 
> Did it rub against the transformer?
 
The photo doesn't show the chrome metal box that the transformer is
mounted in. The HV outputs are in two chrome metal tubes that the tree
plugs into...
 
John :-#)#
 
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
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Digest for sci.electronics.repair@googlegroups.com - 6 updates in 1 topic

9:40 AM Penedão 0 comments
John-Del <ohger1s@gmail.com>: Jul 25 11:00AM -0700

Nice. Did you ever consider building a lexan box to mount it in?
John Robertson <spam@flippers.com>: Jul 25 02:59PM -0700

On 2020/07/25 11:00 a.m., John-Del wrote:
 
> Nice. Did you ever consider building a lexan box to mount it in?
 
No, my family are careful around it and we no longer have a cat...
 
I agree it would be very unfortunate if it ever broke.
 
John :-#)#
Cydrome Leader <presence@MUNGEpanix.com>: Jul 25 11:52PM

> I have new neon sign with a bad transformer (has a short and works sporadically), it is a 5kv 15MA transformer. I bought a new one that is 5kv 30ma and the neon fades towards the end of the run. It is nice and bright the whole run with the original transformer so I am assuming the 30ma vs 15ma is a problem.
 
> Any advice, im having a hard time finding a 5kv 15ma replacement.
 
Well you're overloading the neon tube and may cause damage to it.
 
I found some 4kV 15ma electronic power supplies online. Might work fine.
Fox's Mercantile <jdangus@att.net>: Jul 25 08:48PM -0500

On 7/25/20 6:52 PM, Cydrome Leader wrote:
 
>> Any advice, im having a hard time finding a 5kv 15ma replacement.
 
> Well you're overloading the neon tube and may cause damage to it.
 
> I found some 4kV 15ma electronic power supplies online. Might work fine.
 
As a test, you could put a 330K resistor in series with the neon tube.
That will limit the current to 15 mA.
 
However, the power rating needs to be in excess of 75 watts.
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
Michael Terrell <terrell.michael.a@gmail.com>: Jul 25 07:25PM -0700

As well as the constant high voltage.
adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Jul 26 10:17AM +0100


> On 2020/07/25 11:00 a.m., John-Del wrote:
 
> > Nice. Did you ever consider building a lexan box to mount it in?
 
> No, my family are careful around it and we no longer have a cat...
 
Did it rub against the transformer?
 
--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk
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Digest for sci.electronics.repair@googlegroups.com - 17 updates in 3 topics

9:40 AM Penedão 0 comments
John Robertson <spam@flippers.com>: Jul 24 09:43AM -0700

On 2020/07/24 9:27 a.m., Brian Struckmeier wrote:
> I have new neon sign with a bad transformer (has a short and works sporadically), it is a 5kv 15MA transformer. I bought a new one that is 5kv 30ma and the neon fades towards the end of the run. It is nice and bright the whole run with the original transformer so I am assuming the 30ma vs 15ma is a problem.
 
> Any advice, im having a hard time finding a 5kv 15ma replacement.
 
30ma is more available power, so it is better - the transformer will
handle a larger load. Your transformer may not be putting out 5KV though...
 
This is where an AC/DC HV probe is handy. You can get 10:1 on eBay and
other sources. Look for ones that appear to be well insulated! If it
comes from China don't stand on a cement floor when using it!
 
 
John :-#)#
adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Jul 24 06:36PM +0100

> bright the whole run with the original transformer so I am assuming the
> 30ma vs 15ma is a problem.
 
> Any advice, im having a hard time finding a 5kv 15ma replacement.
 
The extra current may be damaging the electrodes and causing out-gassing
or overheating the tube so the neon pressure rises. Is there a
possibility that there is an adjustable magnetic shunt inside the
transformer that could be adjusted to reduce the current?
 
Please be careful - with those sorts of currents and voltages, your
first mistake could well be your last.
 
 
--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk
John Robertson <spam@flippers.com>: Jul 24 11:20AM -0700

On 2020/07/24 10:36 a.m., Adrian Tuddenham wrote:
> transformer that could be adjusted to reduce the current?
 
> Please be careful - with those sorts of currents and voltages, your
> first mistake could well be your last.
 
Interesting, I did not realize that Neon transformers were current
limiting, behaving somewhat like a ballast on fluorescent lamps:
 
https://www.richieburnett.co.uk/ballast.html
 
--------------(quote)---------------------------------------
 
Neon sign transformers have built-in magnetic shunts which give current
limiting. In its intended use as a supply for neon tube, the high open
circuit voltage of the transformer is used to strike an arc in the neon
tube. Once an arc has formed inside the neon tube, the current must be
limited to prevent overheating of the neon tube and the transformer due
to excessive current flow. (The hotter the arc gets, the more current
flows, so it gets hotter etc…)
 
----------------(end quote)----------------------------------
 
Thanks for the info! Live and learn, eh?
 
John :-#)#
 
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
Mike Coon <gravity@mjcoon.plus.com>: Jul 24 07:29PM +0100

In article <iPKdnZakvr_wu4bCnZ2dnUU7-LfNnZ2d@giganews.com>,
spam@flippers.com says...
 
> ----------------(end quote)----------------------------------
 
> Thanks for the info! Live and learn, eh?
 
> John :-#)#
 
Exactly like a grown-up version of your tiny neon pilot lamp in an AC
power socket with its ballast resistor...
 
Mike.
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 24 03:42PM -0400

On 2020-07-24 14:20, John Robertson wrote:
 
> ----------------(end quote)----------------------------------
 
> Thanks for the info! Live and learn, eh?
 
> John :-#)#
 
HeNe laser supplies are the same way. You have to match them to the tube.
 
Cheers
 
Phil Hobbs
 
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
 
http://electrooptical.net
http://hobbs-eo.com
John Robertson <spam@flippers.com>: Jul 24 03:10PM -0700

On 2020/07/24 11:29 a.m., Mike Coon wrote:
 
> Exactly like a grown-up version of your tiny neon pilot lamp in an AC
> power socket with its ballast resistor...
 
> Mike.
 
I have a Neon Christmas tree (glass tube outline) that was made for my
grandfather by his employees (E.L. Ruddy in Toronto) during the
depression (as Granny told me years ago). Stands about 14 inches tall
and is still working just fine. Haul it out every winter and plug it
into its base.
 
I can post a picture if anyone is interested...
 
John :-#)#
 
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
John-Del <ohger1s@gmail.com>: Jul 24 06:53PM -0700

On Friday, July 24, 2020 at 6:10:37 PM UTC-4, John Robertson wrote:
> into its base.
 
> I can post a picture if anyone is interested...
 
> John :-#)#
 
I certainly wouldn't mind seeing it John.
John Robertson <spam@flippers.com>: Jul 24 07:56PM -0700

On 2020/07/24 6:53 p.m., John-Del wrote:
 
>> I can post a picture if anyone is interested...
 
>> John :-#)#
 
> I certainly wouldn't mind seeing it John.
 
https://flippers.com/images/XmasNeonSmokey.JPG
 
https://flippers.com/images/XmasNeonTree.JPG
 
Old photos, that don't show the metal base. All I have at the moment. It
is sitting on a 1929ish RCA radio, sitting on a 1920s radio speaker
cabinet. Photos taken almost twenty years ago.
 
John :-#)#
Mike Coon <gravity@mjcoon.plus.com>: Jul 25 12:34PM +0100

In article <w7ednSQeHN_6AobCnZ2dnUU7-f_NnZ2d@giganews.com>,
spam@flippers.com says...
 
> >> I have a Neon Christmas tree (glass tube outline) that was made for
my
> It is sitting on a 1929ish RCA radio, sitting on a 1920s radio speaker
> cabinet. Photos taken almost twenty years ago.
 
> John :-#)#
 
How refreshing that the shape has an smidgen of randomness!
 
Mike.
Bob Engelhardt <BobEngelhardt@comcast.net>: Jul 25 08:04AM -0400

On 7/25/2020 7:34 AM, Mike Coon wrote:
> How refreshing that the shape has an smidgen of randomness!
 
> Mike.
 
My thoughts exactly.
 
'Twere mine, I would put it up every year too. To remember grandpa and
because it's cool.
John Robertson <spam@flippers.com>: Jul 25 09:32AM -0700

On 2020/07/25 5:04 a.m., Bob Engelhardt wrote:
 
> My thoughts exactly.
 
> 'Twere mine, I would put it up every year too.  To remember grandpa and
> because it's cool.
 
Exactly. It goes up every year for a month or so...
 
Thanks,
 
John :-#)#
Jeff Urban <jurb6006@gmail.com>: Jul 24 06:57PM -0700

First of all Phil is probably right. But then if you want to try things on your own...
 
The chips you mentioned are probably the clock and BBD. They really should not affect the level of sound.
 
Turn the chorus off and see if you are getting the same volume out of each speaker.
 
If the sound is equal then you need to go right after the BBD circuit. If not it could be in the amp on that side anywhere.
Jeff Urban <jurb6006@gmail.com>: Jul 24 07:15PM -0700

There is an OP AMP right after the BBD, it is set to unity gain. If you have a scope, it should be putting out the same amplitude as what is going in.
 
It is nice to have a generator working in those things but you have to usually resistor the output way down. Where I worked I had a guitar next to me, plugged it in and had to strum it periodically. My stuff stays home now.
 
That print says for a power/gain test go in the return loop jack and you should have equal signal on both sides. You can plug a friggin cassette deck into it really. (one channel) All you have to do is get or make the proper adapter.
Phil Allison <pallison49@gmail.com>: Jul 24 09:32PM -0700

Jeff Urban wrote:
 
============================
 
> First of all Phil is probably right.
 
** You bet he is...
 
> But then if you want to try things on your own...
 
** He might start with the Chorus/ straight switching system. In Chorus mode, one channel handles straight signal while the other the delayed/swept version.
 
Mixing of the two to give the effect occurs in the air beyond the speakers.
If the either channel's level is low, he may still think both speakers are workings when one is not.
 
I use a scope to tell, the delayed signal sounds almost normal until the straight one is added.
 
 
..... Phil
Jeff Urban <jurb6006@gmail.com>: Jul 25 02:51AM -0700

Well like you said but in different words, this takes a tech. One speaker could be half blown. And in a guitar amp post people would not notice much if the amp is only pushing one direction.
 
I say let the guy do it. I think he owns it. If it goes poof then it does.
 
Maybe the guy will buy a scope. I think novices should always start with a CRO, not a raster based one. No digital no nothing.
 
That would ell of the speakers. They both had the same power but one (the right one I think right ?) is half fucked up because maybe something got spilled in it. Shit happens.
 
Well if out OPer here is reading he is probably learning. One of the simplest tests would be to switch the speakers. However we know that is not always feasible. You got two viable choices, mount them reverse. Or just hook it to external speakers. We all have a pair of speakers around.
 
So without a scope he is not even to that point yet, needs a pair.
tdt.algarve@gmail.com: Jul 24 09:52AM -0700

quarta-feira, 18 de Junho de 1997 às 08:00:00 UTC+1, John Hinrichs escreveu:
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> email: hinrichs@artswire.org nextwave@compuserve.com
> voice: +1 213 957 1769 fax: +1 213 962 6710
 
Hello. Still want the phone?
Eli the Bearded <*@eli.users.panix.com>: Jul 24 06:20PM

> quarta-feira, 18 de Junho de 1997 às 08:00:00 UTC+1, John Hinrichs escreveu:
^^^^^^^^^^^^^^^^^^^
>> Would like to buy a Panasonic KXT-8000 Phone Answering Machine.
> Hello. Still want the phone?
 
Twenty three years later. What do you think?
 
Elijah
------
"John Hinrichs obituary" returns a lot of search results
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Brian Struckmeier <bstruckm@gmail.com>: Jul 24 09:27AM -0700

I have new neon sign with a bad transformer (has a short and works sporadically), it is a 5kv 15MA transformer. I bought a new one that is 5kv 30ma and the neon fades towards the end of the run. It is nice and bright the whole run with the original transformer so I am assuming the 30ma vs 15ma is a problem.
 
Any advice, im having a hard time finding a 5kv 15ma replacement.
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Digest for sci.electronics.repair@googlegroups.com - 6 updates in 3 topics

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John-Del <ohger1s@gmail.com>: Jul 20 12:17PM -0700


> >I never heard much difference between brands of EL34s, 6CA7s, and even 8417s I've used in my vintage Fisher integrated amp. They all sounded fine until they became flabby with age.
> Yeah, I almost had a heart attack when I tried posting the name
> brands.
 
 
How did you know I was being literal?
 
 
> The better sounding
> tubes are Psvane brand tubes. The worse sounding tubes are
> Electro-Harmonics.
 
I've used EH EL34s and the 6CA7s in my audio amps and guitar amps, and I thought they were as good as a set of NOS Sylvania 6CA7s I keep on hand. Not to pick on your amp, but I'm not sure that amp is the right device to critique vacuum tubes/valves. Also, I've never listened to (or even seen) a single ended EL34 amp.
 
 

> bias is adjustable?
> Thanks,
> Eric
 
I've never actually owned any EL34 amp that was auto bias, so I never compared them. I do know that if you manually bias the outputs too cold, they become class B and sound like crap, which is why I asked. I bias my guitar amp a little hotter than design spec, and my vintage audio amps just a bit on the cool side, and they sound great, but I do rebias them every few months.
 
Before modding your amp, I would measure the cathode current and see where the tube is running. You should be running close to but not over 100% plate dissipation of the tube you are using. You may have to replace your cathode resistors to get there.
Phil Allison <pallison49@gmail.com>: Jul 20 10:32PM -0700

et...@whidbey.com wrote:
 
=======================
 
> This is the amp: https://www.aliexpress.com/i/1988522234.html
> The amp has no bias adjustment.
 
** That is a pile of Chinese "audiophool bait".
 
Cheap and very nasty, a lo-fi joke.
 
Like I already said - your post is a troll.
 
Like all the others you ever posted.
 
 
 
.... Phil
"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 21 04:32AM -0700

I would be inclined to call the Drongo from Down-Under the only troll here - but that would require it to have magical powers, live in a mountain and steal maidens - all beyond the capacity of this creature.
 
Peter Wieck
Melrose Park, PA
"G. Paul Ziemba" <unp@ziemba.us>: Jul 20 05:01PM

Can anyone explain the electrical principles of the Broan "Quiet Series"
(also called "Allure") range hood fan?
 
This unit was made in 2005. There is an electronic control board
with three relays that appear to activate three blower speeds
(low, medium, high). The blower motor has four wires and there is
a 7.5 uF capacitor involved.
 
There are pushbuttons for the three speeds. Speeds 1 and 3 work correctly.
After 14 years of use, speed 2 (most frequently used speed) worked only
intermittently but did respond to impact adjustment. Now it doesn't even
do that.
 
I can hear a relay click for each of the three speeds. but the motor
does not turn at all for speed 2. I suspect either failed relay contacts
or a bad joint/broken trace, but I haven't gotten a look at the circuit
board yet (pending arrival of new membrane button cover which gets
destroyed when accessing control board).
 
Anyone know how the motor circuit works? Given that there are only
four wires it seems to be a bit more complex than common-cap-1-2-3.
 
Oh, and although it would be easy to throw parts at it, the control
board retails for $200. I'd be happer to see if I can resolder or
throw a $5 relay at it.
 
thanks!
--
G. Paul Ziemba
FreeBSD unix:
10:11AM up 50 days, 17:52, 41 users, load averages: 0.16, 0.18, 0.22
"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 21 03:47AM -0700

Three windings on the motor and a common. Most typically, such things are one/two/both, but in your case, it is one/two/three. So:
 
a) determine the motor voltage - likely the same as the line voltage.
b) If you can remove the motor from the circuit, do so.
c) Determine the common.
d) Apply voltage at each winding - additionally, not sequentially - and note if the motor speed increases as expected.
f) If so, the relay is likely bad. 15 years is not a bad service life.
g) If not, the motor likely bad - and it will be a close-run thing whether to replace the hood or just the motor.
 
 
Best of luck.
 
Peter Wieck
Melrose Park, PA
bleachbot <bleachbot@httrack.com>: Jul 21 07:32AM +0200

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etpm@whidbey.com: Jul 19 12:39PM -0700

One of the EL34 tubes in my amp was making intermittent noise so I
bought a couple new matched EL 34 tubes and put them in the amp. They
sounded OK but not great. At first I thought it was the particular
recording that was sounding so bad because the recording was bad. It
was the Happy Trails album by Quicksilver Messaging Service. The
original recording just wasn't the best quality.
Then about a week later I was listening to some Herbie Hancock and
the sound was kinda muddy or muffled sounding. It did not have the
same clarity as it did with the first set of tubes. So I swapped in
the old pair and and there was a marked difference in the quality of
the sound. I was really surprised at the difference.
Now I gotta shop for some better tubes. What is done in the
manufacturing of tubes that can have such a big difference?
Eric
John-Del <ohger1s@gmail.com>: Jul 19 04:04PM -0700

> Now I gotta shop for some better tubes. What is done in the
> manufacturing of tubes that can have such a big difference?
> Eric
 
I can't answer your question, but would it have killed you to put the brand names of the original set of outputs and the replacement set you installed, or the amp you're using?
 
Also, did you bias the new tubes properly? If they're running too cold they'll sound like crap.
 
I never heard much difference between brands of EL34s, 6CA7s, and even 8417s I've used in my vintage Fisher integrated amp. They all sounded fine until they became flabby with age.
Phil Allison <pallison49@gmail.com>: Jul 20 02:23AM -0700

John-Del = Dope wrote:
 
===========================
 
> I can't answer your question,
 
 
* It ain't a Q - it's a troll.
 
 
but would it have killed you to put the brand names of the original set of outputs and the replacement set you installed, or the amp you're using?
 
** Nowadays, there are only two kinds of *new* EL34s, Chinese and Russian.
 
The former suck while the latter are mostly OK.

 
> I never heard much difference between brands of EL34s, 6CA7s,
> and even 8417s I've used in my vintage Fisher integrated amp.
> They all sounded fine until they became flabby with age.
 
** Happens to people too....
 
 
 
 
... Phil
etpm@whidbey.com: Jul 20 08:57AM -0700

On Sun, 19 Jul 2020 16:04:12 -0700 (PDT), John-Del <ohger1s@gmail.com>
wrote:
 
 
>I can't answer your question, but would it have killed you to put the brand names of the original set of outputs and the replacement set you installed, or the amp you're using?
 
>Also, did you bias the new tubes properly? If they're running too cold they'll sound like crap.
 
>I never heard much difference between brands of EL34s, 6CA7s, and even 8417s I've used in my vintage Fisher integrated amp. They all sounded fine until they became flabby with age.
Yeah, I almost had a heart attack when I tried posting the name
brands. But I'm not the type who gives up easily. The better sounding
tubes are Psvane brand tubes. The worse sounding tubes are
Electro-Harmonics. Oh crap! My heart! Call 911!
This is the amp: https://www.aliexpress.com/i/1988522234.html
The amp has no bias adjustment. I know that different circuits are
used for adjustable bias and auto bias. Could it really make that big
of a difference? Should I consider modding the circuit so that the
bias is adjustable?
Thanks,
Eric
Fox's Mercantile <jdangus@att.net>: Jul 20 11:30AM -0500

> Could it really make that big of a difference? Should I
> consider modding the circuit so that the bias is adjustable?
 
Yes
 
 
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
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