sci.electronics.repair
http://groups.google.com/group/sci.electronics.repair?hl=en

sci.electronics.repair@googlegroups.com

Today's topics:

* 3.5mm stereo headphone socket that isn't. - 7 messages, 5 authors
http://groups.google.com/group/sci.electronics.repair/t/28320987875a2efc?hl=en
* HDMI Dead on Panasonic TCP50S2 Plasma TV - 11 messages, 5 authors
http://groups.google.com/group/sci.electronics.repair/t/5ac9f3bf982f8aef?hl=en
* HP IC, Unobtanium ? - 7 messages, 4 authors
http://groups.google.com/group/sci.electronics.repair/t/5afcf62282f737a8?hl=en
* SEO Company in Chicago - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/7d4c35bab62e83a9?hl=en

==============================================================================
TOPIC: 3.5mm stereo headphone socket that isn't.
http://groups.google.com/group/sci.electronics.repair/t/28320987875a2efc?hl=en
==============================================================================

== 1 of 7 ==
Date: Tues, Feb 25 2014 9:27 am
From: etpm@whidbey.com


On Tue, 25 Feb 2014 02:54:51 -0000, "Arfa Daily"
<arfa.daily@ntlworld.com> wrote:

>
>
><etpm@whidbey.com> wrote in message
>news:c8umg9leagq2ip4cnifs0viip0pu4v8v9s@4ax.com...
>> On Mon, 24 Feb 2014 01:49:17 -0000, "Arfa Daily"
>> <arfa.daily@ntlworld.com> wrote:
>>
>>>
>>>
>>><etpm@whidbey.com> wrote in message
>>>news:qq1lg9p1d3g6oajdipj6f039rl9p22covb@4ax.com...
>>>> On Sun, 23 Feb 2014 13:12:56 -0000, "Arfa Daily"
>>>> <arfa.daily@ntlworld.com> wrote:
>>>>
>>>>>
>>>>>
>>>>>>>> http://www.avast.com
>>>>>>>>
>>>>>>>Which part of the message saying "The Schurter is 18mm long" did you
>>>>>>>not
>>>>>>>understand ??
>>>>>> I did understand the message. I just noticed that the name "Schurter
>>>>>> is pretty close to the word "shorter" and I thought it was funny that
>>>>>> the shorter one was longer. Sheesh!
>>>>>> Etic
>>>>>>
>>>>>> ---
>>>>>
>>>>>
>>>>>That was quite clever humour - along the lines of "Don't call me Shirley
>>>>>..."
>>>>>
>>>>>But I have to say that it did go over my head until you explained it ...
>>>>>d;-)
>>>>>
>>>>>Arfa
>>>> Greetings Arfa,
>>>> Thanks for the compliment. When I was little I didn't get puns. I was
>>>> just too literal thinking. When explained to me I could see the play
>>>> on words but the humor escaped me. Then one day I "got" a pun. I must
>>>> have been about 10 or 11. Since then I see puns all over the place.
>>>> Cheers,
>>>> Eric
>>>>
>>>
>>>I think I've become too used to taking stuff literally on here, and not
>>>looking for the humour. You'll notice the different spelling of the word,
>>>as
>>>I am in the U.K. Over the years, I've seen many cases of what was
>>>intended
>>>to be humour being misinterpreted by the time it reached the other side of
>>>the pond, and some pretty violent arguments breaking out as a result, a
>>>few
>>>of which I've been involved in ... :-)
>>>
>>>The last such that I can remember was a typically British throw-away
>>>comment
>>>about a Bulova Accutron wristwatch, which was seen by everyone this side
>>>as
>>>tongue-in-cheek humour, but was taken as a proper insult by the American
>>>OP,
>>>and ultimately a number of other regular U.S. posters who pitched in their
>>>two penn'orth. Since then, there doesn't seem to have been much attempt at
>>>humour from either side, and I think that's why it went over my head - I
>>>just wasn't looking for it or expecting it !
>>>
>>>Still, good to see some back. Keep it up sir !
>>>
>>>Arfa
>> The British and American slang differences are a great source of
>> humo(u)r. My brother has a friend who was visiting her husband's
>> relatives in Britain. These folks were pretty high class, pretty
>> proper. At the end of a good meal she exclaimed that she was
>> "stuffed". After comment only silenced ensued. Later that evening her
>> husband told her why her comment was offensive. This makes me think
>> about how much fun the Brits must have had when shag carpet was so
>> popular here in the US.
>> Eric
>>
>> ---
>>
>And "bumming a fag" for begging a cigarette and "knocking me up" for
>asking for a wake-up call (by banging on the bedroom door, of course ... )
>d:-)
>
>( I speak fluent American as I visit quite often ... !)
>
>Arfa
I think the slang terms "Taking the piss" and "He's pissed" are pretty
funny when I think about how they are used where I live. And I've
always wondered about "Bloody". How it became a bad word. And what
happens when someone or something is covered with blood? What do you
say? I like steak rare. I will order it bloody. In a nice restaurant
in London I suppose it woule be a faux pas to order a "bloody steak".
I think I need to look up the etymology of bloody.
Eric

---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com





== 2 of 7 ==
Date: Tues, Feb 25 2014 5:51 pm
From: "Arfa Daily"



Still, over and
> done with, and no point in resurrecting it all again, so we'll just leave
> it
> there, shall we ?
>
> Thank you for clarifying, but I can't leave it there.
>
> When written out, /without/ modification (such as verbal inflection or
> tone of voice), "crap design" has only one meaning in American or British
> English -- a criticism.
>
> Now, if the person had written "crap design :)" -- there would have been
> no argument.
>

Please William, for once, just leave it as I asked, will you ?

Thanks

Arfa





== 3 of 7 ==
Date: Tues, Feb 25 2014 6:14 pm
From: "Arfa Daily"




>>
>>Arfa
> I think the slang terms "Taking the piss" and "He's pissed" are pretty
> funny when I think about how they are used where I live. And I've
> always wondered about "Bloody". How it became a bad word. And what
> happens when someone or something is covered with blood? What do you
> say? I like steak rare. I will order it bloody. In a nice restaurant
> in London I suppose it woule be a faux pas to order a "bloody steak".
> I think I need to look up the etymology of bloody.
> Eric
>
> ---

"He's pissed" can have two meanings, one of which I'm sure we share, and
that is being a bit mad about something. It's abbreviated from "pissed off".
But here, it also means being drunk, and the process of becoming so is
"getting pissed". But getting pissed can of course also mean becoming a bit
angry ... :-)

"Getting hammered" or "He's hammered" are also phrases for drunkenness here.
It can also refer to being under the influence of drugs.

Bloody is a funny one. I've never looked into its origins as a swear word.
It is very mild though, and is often used in conjunction with another word
as an outburst of exasperation or shock as in "Bloody hell!" or "Bloody
Norah" - and no, I've no idea who 'Norah' was ...

Yes, a person covered in blood can be described as bloody, as can a rag or a
handprint or whatever. It's commonly used in that context.

If you asked for a bloody steak in a decent restaurant, they might look at
you a bit sideways, but would understand what you wanted. In anything less
that a decent one, they would probably just not understand you at all, and
would think that you were swearing. Some restaurants won't even serve a
bloody steak, such is the Health and Safety madness here now. All the same
definitions of steak temperature apply here as well as in the U.S. but the
same temperature is normally a little less here, so if you ordered a 'rare'
steak here, it would normally be a bit pinker than you would be used to if
you asked for it rare your side of the pond. If you ask for it very rare, it
will normally be a little bloody in the middle. If you want a piece of meat
that a vet could bring back to life, you can ask for a 'blue' steak. This
has been really quickly flash cooked, and is only about 2 points to the
right of raw through to the core.

Arfa





== 4 of 7 ==
Date: Tues, Feb 25 2014 6:21 pm
From: dplatt@coop.radagast.org (David Platt)


In article <q6cPu.781$XF6.696@fx31.am4>,
Arfa Daily <arfa.daily@ntlworld.com> wrote:

>"Getting hammered" or "He's hammered" are also phrases for drunkenness here.
>It can also refer to being under the influence of drugs.

I believe there's also a sexual connotation, in some contexts.

>Bloody is a funny one. I've never looked into its origins as a swear
> word.

One theory is that it comes from "B'r Lady" or "By our Lady" (a
sacrilegious reference to the Virgin Mary). There are lots of
competing theories... it seems as if nobody really knows for sure.

> If you ask for it very rare, it
>will normally be a little bloody in the middle. If you want a piece of meat
>that a vet could bring back to life, you can ask for a 'blue' steak. This
>has been really quickly flash cooked, and is only about 2 points to the
>right of raw through to the core.

A college friend of mine used to use the instruction "Show it to a
picture of a flame for ten seconds."






== 5 of 7 ==
Date: Wed, Feb 26 2014 6:28 am
From: "William Sommerwerck"


> I've always wondered about "Bloody". How it became a bad word.

"Bloody" is a corruption of "by our Lord". It is "bad" because it's considered
disrespectful to use it as a derogatory term.





== 6 of 7 ==
Date: Wed, Feb 26 2014 6:33 am
From: "William Sommerwerck"


The Gilbert & Sullivan opera "Ruddigore" was originally titled "Ruddygore".
People actually refused to see it because of the resemblance of "ruddy" to
"bloody". So Gilbert changed the name.

When someone asked Gilbert "How's old 'Bloodygore' coming?", he replied "If I
say I like your ruddy complexion -- which I do -- it does not mean I like your
bloody cheek -- which I don't!"





== 7 of 7 ==
Date: Wed, Feb 26 2014 7:01 am
From: "Gareth Magennis"



"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
news:lektv2$kkh$1@dont-email.me...
> The Gilbert & Sullivan opera "Ruddigore" was originally titled
> "Ruddygore". People actually refused to see it because of the resemblance
> of "ruddy" to "bloody". So Gilbert changed the name.
>
> When someone asked Gilbert "How's old 'Bloodygore' coming?", he replied
> "If I say I like your ruddy complexion -- which I do -- it does not mean I
> like your bloody cheek -- which I don't!"



When I was a lad in the UK, many people commonly chose the word "ruddy" as a
somewhat more polite way of swearing than using the very offensive (at the
time) "bloody".



Gareth.







==============================================================================
TOPIC: HDMI Dead on Panasonic TCP50S2 Plasma TV
http://groups.google.com/group/sci.electronics.repair/t/5ac9f3bf982f8aef?hl=en
==============================================================================

== 1 of 11 ==
Date: Tues, Feb 25 2014 9:38 pm
From: Mike Tomlinson


En el artículo <uwqgkws4h.fsf@repairfaq.org>, Samuel M. Goldwasser
<sam@repairfaq.org> escribió:

> It's only when it goes to
>paly the disc that the error is produced and no video.

So the TV shows the usual menus, etc. from the BD player, but only
throws an error when you try and play a disc?

Some form of weird copy protection? Tried a known working disc?

Could the TV have had an over-the0-eir software update without yo
knowing, which has broken something?

--
(\_/)
(='.'=)
(")_(")




== 2 of 11 ==
Date: Tues, Feb 25 2014 9:39 pm
From: Mike Tomlinson


En el artículo <alpine.LNX.2.02.1402241840240.8574@darkstar.example.org>
, Michael Black <et472@ncf.ca> escribió:

>Check the FAQ

Sam *wrote* the FAQ :-)

--
(\_/)
(='.'=)
(")_(")




== 3 of 11 ==
Date: Wed, Feb 26 2014 11:33 am
From: Michael Black


On Wed, 26 Feb 2014, Mike Tomlinson wrote:

> En el artículo <alpine.LNX.2.02.1402241840240.8574@darkstar.example.org>
> , Michael Black <et472@ncf.ca> escribió:
>
>> Check the FAQ
>
> Sam *wrote* the FAQ :-)
>
Which is precisely why I put it in there.

Michael




== 4 of 11 ==
Date: Wed, Feb 26 2014 1:29 pm
From: sam@repairfaq.org (Samuel M. Goldwasser)


Mike Tomlinson <mike@jasper.org.uk> writes:

> En el artículo <uwqgkws4h.fsf@repairfaq.org>, Samuel M. Goldwasser
> <sam@repairfaq.org> escribió:
>
> > It's only when it goes to
> >paly the disc that the error is produced and no video.
>
> So the TV shows the usual menus, etc. from the BD player, but only
> throws an error when you try and play a disc?

No, the TV shows nothing through any of the HDMI ports. But the BD player
displays an error once it starts to play. It continudes to play with the
U72 or U73 error displayed, but nothing shows up on the screen.

What it does do it automagically turn on the TV via the VIERA link through
the HDMI, so something on the HDMI is working. Just no picture.

> Some form of weird copy protection? Tried a known working disc?

This is with know working DVDs.

> Could the TV have had an over-the-eir software update without yo
> knowing, which has broken something?

Not likely. I don't think this TV can update firmware off air. There is
no Internet connection.

Thanks for your thoughts!

--
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.





== 5 of 11 ==
Date: Wed, Feb 26 2014 1:30 pm
From: sam@repairfaq.org (Samuel M. Goldwasser)


Mike Tomlinson <mike@jasper.org.uk> writes:

> En el artículo <alpine.LNX.2.02.1402241840240.8574@darkstar.example.org>
> , Michael Black <et472@ncf.ca> escribió:
>
> >Check the FAQ
>
> Sam *wrote* the FAQ :-)

:)

Too bad there isn't really anything on modern flat screen TVs in there....

--
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.




== 6 of 11 ==
Date: Wed, Feb 26 2014 1:30 pm
From: sam@repairfaq.org (Samuel M. Goldwasser)


Michael Black <et472@ncf.ca> writes:

> On Wed, 26 Feb 2014, Mike Tomlinson wrote:
>
> > En el artículo <alpine.LNX.2.02.1402241840240.8574@darkstar.example.org>
> > , Michael Black <et472@ncf.ca> escribió:
> >
> >> Check the FAQ
> >
> > Sam *wrote* the FAQ :-)
> >
> Which is precisely why I put it in there.

Yeah, actually a suggestion like that isn't silly. I often forget what's
in the FAQs! ;-)

--
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.




== 7 of 11 ==
Date: Wed, Feb 26 2014 2:32 pm
From: Michael Black


On Wed, 26 Feb 2014, Samuel M. Goldwasser wrote:

> Mike Tomlinson <mike@jasper.org.uk> writes:
>
>> En el artículo <alpine.LNX.2.02.1402241840240.8574@darkstar.example.org>
>> , Michael Black <et472@ncf.ca> escribió:
>>
>>> Check the FAQ
>>
>> Sam *wrote* the FAQ :-)
>
> :)
>
> Too bad there isn't really anything on modern flat screen TVs in there....
>
It is too bad, and I couldn't figure out how to fit that in without making
it sound negative. The FAQ is still great, except it's not kept up with
the present (or future, depending on how you look at it).

The neat thing is, LCD tv sets and monitors are so much easier to work on,
at least the boards, than in the days of CRT tv sets and monitors, where
the main board had endless wires and you had to pull out the board in
order to do any work on it. An LCD monitor has two, or maybe sometimes
just one, board, and they are so easy to remove to work on.

Michael




== 8 of 11 ==
Date: Wed, Feb 26 2014 3:32 pm
From: John-Del


On Wednesday, February 26, 2014 4:29:18 PM UTC-5, Samuel M. Goldwasser wrote:

But the BD player
>
> displays an error once it starts to play. It continudes to play with the
>
> U72 or U73 error displayed, but nothing shows up on the screen.

Geez Sam, did you try another DVD player or game system? You may have a bad Blu player as well as just one HDMI port inop....

I've seem a bunch of Pannys with a single bad HDMI input.





== 9 of 11 ==
Date: Wed, Feb 26 2014 5:11 pm
From: jurb6006@gmail.com


If a firmware update is not available for it or is but doesn't fix it you need a main board.




== 10 of 11 ==
Date: Wed, Feb 26 2014 8:48 pm
From: Michael Black


On Wed, 26 Feb 2014, jurb6006@gmail.com wrote:

> If a firmware update is not available for it or is but doesn't fix it
> you need a main board.
>
Well maybe we'll get a new Repair Brief out of this, I remember when they
were posted here. The neat things Sam would find, and then get going.

Michael





== 11 of 11 ==
Date: Wed, Feb 26 2014 9:31 pm
From: jurb6006@gmail.com


I'm pretty sure about the signal not getting through the big damn chip. The question is whether it is a software or hardware problem. If you go to shopjimmys and look at a picture of the main board fro that model, alot of those traes from the HDMI jacks go straight to a big BGA flat thing with a heatsink. The page is here :

http://www.shopjimmy.com/panasonic-txn-a1lquus-a-board.htm

Next to each HDMI jack is a little SMD transistor, no doubt a buffer for whatever data an HDMI device wants to tell the micro. Now if plugging in a modern device (which he has) causes the set to switch to that input (which it did) and it does not produce a picture, the test is inconclusive. the IC that selects the HDMI input could simply be bad, but on the other hand it may not have neen initialized properly. this can be caused by a bad micro, or more likely corrupt data. the corrupt data can be caused by a defective EPROM.

Now actually, EPROMS don't go bad as often as the used to, and I think that shitty power supplies cause alot of data corruption. they depend on specific capacitances in electrolytics for an orderly power down sometimes, which ois shitty engineering because the never gain ESR and/or lose capacity at the same rate over time. In a three year old unit, the screwup could have happened once when turned on cold in a certain mode, or whatever. It depends on too much to be analysable effectively withoput a hell of alot of information and equipment we do not have.

If I could reverse engineer a data port on the thing and had a properly working unit, I would indeed try to load the data from the EPROM in the workiung unit into the non-working unit. I would say that most likely it would fix it.

I would then consider modifying the power supply to make a recurrance less likely. Most likely I would be forced to trust the engineers to have designed it so that a sustained Vcc or Vdd to the micro and EPROM would not damage the ports by having the other supplies slam down on the protection diodes in all the other ICs.

Of course all this is not going to happen. I've never dealt with load EPROMS manually using a PC. I know RCA's Chipper Check software has suck a function. I also know tha tin other electronic fields it is done sometimes, but they are working on expensive equipment that justifies the cost of all this horseshit. If we could get EPROM images when these sets are new, that owuld not be so bad, but where the hell are you going to find the exact same model, and I mean exact. Just because it has the same model number does not mean it is the same model. I have found this out enough times...

So we are down to replacing the board, because if it is a software problem you can change ALL the parts and not fix it. Got one someone broke in half ? go ahead and just change the EPROM. It is SMD but it's only eight pins. It is doable, even for us old guys who can't see.

But get one.





==============================================================================
TOPIC: HP IC, Unobtanium ?
http://groups.google.com/group/sci.electronics.repair/t/5afcf62282f737a8?hl=en
==============================================================================

== 1 of 7 ==
Date: Tues, Feb 25 2014 10:05 pm
From: jurb6006@gmail.com


Got a 1725a here that needs the vertical IC. It's designation is A5U2 and I THINK the part number is 5061-0024. The manual is a shitty scan, but any other numbers I can get out of it are too off the wall, at least that number googles back to SOMETHING.

The Thing about this is that it is missing. Is it a high failure rate part ? Another question I have is if it fits any better scopes. I assume of course they would be HP, but why would someone take it out unless either it was bad, or they wanted it to use in another unit. If they used it in another unit, what would that be that would warrant effectively scrapping this one ? A higher end scope using the same part ?

OK, I could see in a business setting where it owuld not be feasible to replace the thing even with the same model because of anal regulations, but is that a reasonable assumption ? Also, if they fail that much, maybe I should be leary of a used one. I assume there are no new ones.

According to the print, this thing only has four transistors and a half dozen resitors in it. Think there is a possibility of some sort of retrofit ? Like building the equaivalent out of discrete parts ? Might not be absolutely perfect but the thing is useless now.

Either that or part it out. Are the other parts worth much ?




== 2 of 7 ==
Date: Tues, Feb 25 2014 10:52 pm
From: "Tom Miller"



<jurb6006@gmail.com> wrote in message
news:e80696ea-d3ea-4eba-ad19-74b90c6353f2@googlegroups.com...
Got a 1725a here that needs the vertical IC. It's designation is A5U2 and I
THINK the part number is 5061-0024. The manual is a shitty scan, but any
other numbers I can get out of it are too off the wall, at least that number
googles back to SOMETHING.

The Thing about this is that it is missing. Is it a high failure rate part ?
Another question I have is if it fits any better scopes. I assume of course
they would be HP, but why would someone take it out unless either it was
bad, or they wanted it to use in another unit. If they used it in another
unit, what would that be that would warrant effectively scrapping this one ?
A higher end scope using the same part ?

OK, I could see in a business setting where it owuld not be feasible to
replace the thing even with the same model because of anal regulations, but
is that a reasonable assumption ? Also, if they fail that much, maybe I
should be leary of a used one. I assume there are no new ones.

According to the print, this thing only has four transistors and a half
dozen resitors in it. Think there is a possibility of some sort of retrofit
? Like building the equaivalent out of discrete parts ? Might not be
absolutely perfect but the thing is useless now.

Either that or part it out. Are the other parts worth much ?

++++++++++++++++++++++++++++++++++++++++++++=


HP part number 5081-3024

Used also in the 1710B and the 1722B.






== 3 of 7 ==
Date: Wed, Feb 26 2014 4:21 am
From: Miguel Giménez


El 26/02/2014 7:05, jurb6006@gmail.com escribió:
> Got a 1725a here that needs the vertical IC. It's designation is A5U2
> and I THINK the part number is 5061-0024. The manual is a shitty
> scan, but any other numbers I can get out of it are too off the wall,
> at least that number googles back to SOMETHING.
>
> The Thing about this is that it is missing. Is it a high failure rate
> part ? Another question I have is if it fits any better scopes. I
> assume of course they would be HP, but why would someone take it out
> unless either it was bad, or they wanted it to use in another unit.
> If they used it in another unit, what would that be that would
> warrant effectively scrapping this one ? A higher end scope using the
> same part ?
>
> OK, I could see in a business setting where it owuld not be feasible
> to replace the thing even with the same model because of anal
> regulations, but is that a reasonable assumption ? Also, if they fail
> that much, maybe I should be leary of a used one. I assume there are
> no new ones.
>
> According to the print, this thing only has four transistors and a
> half dozen resitors in it. Think there is a possibility of some sort
> of retrofit ? Like building the equaivalent out of discrete parts ?
> Might not be absolutely perfect but the thing is useless now.
>
> Either that or part it out. Are the other parts worth much ?
>

Here you have a retrofit; it makes me remember the "Back to the future
part III" time machine repair with 1955 components.

Schematic:

http://elektrotanya.com/files/forum/2013/07/HP5081-3024%20replacement.jpg

Forum (in hungarian):

http://elektrotanya.com/?q=hu/content/hp-1720a-oszcilloszkop-javitasa

--
Saludos
Miguel Giménez




== 4 of 7 ==
Date: Wed, Feb 26 2014 7:17 am
From: jurb6006@gmail.com


>"HP part number 5081-3024

Used also in the 1710B and the 1722B. "

Thanks. Having the right part number helps no matter what. I notice both of those numbers are lower than 1725, should I assume then that the 1725 is the best of the "family" ? If that's the case, the mystery remains of why this one got the axe. Of course the thing might have just went bad, it does happen.




== 5 of 7 ==
Date: Wed, Feb 26 2014 7:34 am
From: jurb6006@gmail.com


>"Schematic:

http://elektrotanya.com/files/forum/2013/07/HP5081-3024%20replacement.jpg "

WOW ! Now that might just save the day. Thanks. I notice a dot RO in the picture there, does that mean Romania ? I've been told by some from across the pond that alot of parts are very hard to get, it's not like the US. They have had to become more resourceful as a result.

So it pretty much boils down to do this unless I can scare up a jubnker with the IC. This looks highly doable. the only thing now is the selection of the MOSFETs. Voltage, current and frequency response are obvious, the only question is gain.

It's obvious that the 1K resistors set the gain to some extent, but the highest gain possible is not always best in tis type of application. Or is it ? a thousand ohms isn't much, maybe the highest gain within reason would be best. If you want to make a suggestion I am highly suggestable. The main thing I know is to get devices that will work in the linear region. That will probably mean looking at some datasheets because most linear applications I've seen are either audio or video amps and neither of them are going to have the frequaency response for this. At least not necessarily. Also, surely the devices exist, it's just that I haven't seen them in the stuff I've worked on.

I actually thought of a retrofit myself, but I was going to stick more to the original, using bipolar. Of course that was not thiknking outside the box in a way - we only need this to do a certain thing, if FETs work, use them and make it easier. I would guess devices like that were not available when they built that unit, but they are now !

:-)




== 6 of 7 ==
Date: Wed, Feb 26 2014 8:06 am
From: amdx


On 2/26/2014 9:34 AM, jurb6006@gmail.com wrote:
>> "Schematic:
>
> http://elektrotanya.com/files/forum/2013/07/HP5081-3024%20replacement.jpg "
>
> WOW ! Now that might just save the day. Thanks. I notice a dot RO in the picture there, does that mean Romania ? I've been told by some from across the pond that alot of parts are very hard to get, it's not like the US. They have had to become more resourceful as a result.
>
> So it pretty much boils down to do this unless I can scare up a jubnker with the IC. This looks highly doable. the only thing now is the selection of the MOSFETs. Voltage, current and frequency response are obvious, the only question is gain.
>
> It's obvious that the 1K resistors set the gain to some extent, but the highest gain possible is not always best in tis type of application. Or is it ? a thousand ohms isn't much, maybe the highest gain within reason would be best. If you want to make a suggestion I am highly suggestable. The main thing I know is to get devices that will work in the linear region. That will probably mean looking at some datasheets because most linear applications I've seen are either audio or video amps and neither of them are going to have the frequaency response for this. At least not necessarily. Also, surely the devices exist, it's just that I haven't seen them in the stuff I've worked on.
>
> I actually thought of a retrofit myself, but I was going to stick more to the original, using bipolar. Of course that was not thinking outside the box in a way - we only need this to do a certain thing, if FETs work, use them and make it easier. I would guess devices like that were not available when they built that unit, but they are now !
>
> :-)
>
Have you ask for a quote from the 100+ companies that won't give you
a price online.
I found a couple of others looking to replace the same ic in the same
scope. You might be better off building it yourself, for reliability.
Mikek




== 7 of 7 ==
Date: Wed, Feb 26 2014 11:05 pm
From: jurb6006@gmail.com


>" Have you ask for a quote from the 100+ companies that won't give you
a price online. "

You mean the ones you send your email address to and if they ever come up with one you have to buy 100,000 of them ? No, I didn't bother doing that.

>" I found a couple of others looking to replace the same ic in the same
scope. You might be better off building it yourself, for reliability. "

Not a bad idea really. Any one I get now would be used. The problem now is finding the right MOSFETs. I bet recalibrating it will be loads of fun. Actually it might not be all that bad. The HF response will probably be better if anything. I might have to remove some of the peaking caps or something if they won't adjust down enough. Then if the gain is really up there of course then I might need to change some resistors. They got the internal 50 ohm changeed to a 47, but that won't mean shit to differential mode. I hope the static plate voltages come close enough ! Then comes getting the thing straight.





==============================================================================
TOPIC: SEO Company in Chicago
http://groups.google.com/group/sci.electronics.repair/t/7d4c35bab62e83a9?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Feb 26 2014 6:35 am
From: kjonmarket.seo1@gmail.com


To stay in the competition commonly what organizations prefer is to go for advertisements programs like pay for every click. Possibly it can help in getting favorable outcome,
http://kjonmarket.com/services1/search-engine-optimization/

but it cut down the profits of any organization up to a great extent because of costs that cannot be recovered. Also there might be a probability of issues like limits on visitors and fraud.




==============================================================================

You received this message because you are subscribed to the Google Groups "sci.electronics.repair"
group.

To post to this group, visit http://groups.google.com/group/sci.electronics.repair?hl=en

To unsubscribe from this group, send email to sci.electronics.repair+unsubscribe@googlegroups.com

To change the way you get mail from this group, visit:
http://groups.google.com/group/sci.electronics.repair/subscribe?hl=en

To report abuse, send email explaining the problem to abuse@googlegroups.com

==============================================================================
Google Groups: http://groups.google.com/?hl=en