PRC as a amplifier in GPS question.

[Phil Allison]

Adrian Jansen wrote:

I know its fun to play with old gear, but realistically, you can buy
something like a modern Rigol scope for around $400 or so, and it will
work perfectly for troubleshooting on old audio circuits,

** Along with my BWD CROs I also own a Rigol DE1052E - $405 delivered from HK.

However, I found it near useless for service work on old or new audio electronics. The Rigol only gets dragged out for special jobs and unusual measurements that analogue scopes can't do.

While you might get a replacement tube to work, what about all those
dried out electrolytic caps in the power supply ?

** Very likely that are few or none of them in a 1970s BWD.

> To say nothing of the carbon composition resistors,

** Ditto.


> Those ancient BWD scopes were never very good,

** Oh really ??

Compared to famous brand scopes at mayt times the prices, BWDs hold their own, compared to the vast majority of Asian scopes at similar prices that are way ahead.

FYI, *all* BWD scopes have magnetic shielded CRTs, an essential item few Asian scopes include and low priced ones never did.

I guess the question is whether you want a tool or a project.

** My I guess is the OP thinks he can have both and Tasmania chucked in for sixpence.

FFS the dope still has not even posted the wanted CRT's number.


..... Phil

 

[Gordon Levi]

Phil Allison <pallison49@gmail.com> wrote:

Adrian Jansen wrote:

I know its fun to play with old gear, but realistically, you can buy
something like a modern Rigol scope for around $400 or so, and it will
work perfectly for troubleshooting on old audio circuits,


** Along with my BWD CROs I also own a Rigol DE1052E - $405 delivered from HK.

However, I found it near useless for service work on old or new audio electronics.

Why? This thread reminded me that I have a BWD 509B that I never use
so I thought I would dispose of it and buy a digital scope in the
unlikely event that I felt the need to use a scope again. Would you
advise me to keep it if the most likely use was for audio?
> The Rigol only gets dragged out for special jobs and unusual measurements that analogue scopes can't do.

 

[Phil Allison]

Gordon Levi wrote:

Phil Allison <pallison49@gmail.com> wrote:

Adrian Jansen wrote:

I know its fun to play with old gear, but realistically, you can buy
something like a modern Rigol scope for around $400 or so, and it will
work perfectly for troubleshooting on old audio circuits,


** Along with my BWD CROs I also own a Rigol DE1052E - $405 delivered from HK.

However, I found it near useless for service work on old or new audio electronics.

Why?

** Having grown up using analogue scopes, I am not happy to see stuff presented on the screen that simply is not there in the device under test. Gritty looking traces and the constant fear ofseeing artefacts like aliasing are a serious distraction - cos they closely resemble non existent faults.

I have also grown very accustomed to the image on the screen being presented in "real time" - so neither delayed in arriving or staying there after the signal has gone. The Rigol hangs on to the last screen for several seconds after the signal has stopped completely ruining the usual procedure for checking out noisy switches and connectors.

But maybe the worst thing is that while analogue scopse have constant bandwidth (like 50MHz) on all sweep ranges, DSOs do not. At typical audio he sweep speeds like 5mS per div the viewable bandwidth is barely the audio band. DSOs have real problems with displaying WIDE band signals correctly.

For example, a low frequency, fast square wave has invisible rises and falls on an analogue scope - not so on a DSO. You have to play with the sweep control to get any idea how fast the rise time is and hence the bandwidth of the circuit on test.

This thread reminded me that I have a BWD 509B that I never use
so I thought I would dispose of it and buy a digital scope in the
unlikely event that I felt the need to use a scope again. Would you
advise me to keep it if the most likely use was for audio?

** Absolutely.

The 509B is a nifty little scope and a pleasure to use compared to a tedious, over complicated, fussy Rigol DSO.



.... Phil

 

[Phil Allison]

Adrian Jansen wrote:

Phil Allison wrote:


** Having grown up using analogue scopes, I am not happy to see stuff presented on the screen that simply is not there in the device under test. Gritty looking traces and the constant fear ofseeing artefacts like aliasing are a serious distraction - cos they closely resemble non existent faults.

I have also grown very accustomed to the image on the screen being presented in "real time" - so neither delayed in arriving or staying there after the signal has gone. The Rigol hangs on to the last screen for several seconds after the signal has stopped completely ruining the usual procedure for checking out noisy switches and connectors.

But maybe the worst thing is that while analogue scopse have constant bandwidth (like 50MHz) on all sweep ranges, DSOs do not. At typical audio he sweep speeds like 5mS per div the viewable bandwidth is barely the audio band. DSOs have real problems with displaying WIDE band signals correctly.

For example, a low frequency, fast square wave has invisible rises and falls on an analogue scope - not so on a DSO. You have to play with the sweep control to get any idea how fast the rise time is and hence the bandwidth of the circuit on test.


This thread reminded me that I have a BWD 509B that I never use
so I thought I would dispose of it and buy a digital scope in the
unlikely event that I felt the need to use a scope again. Would you
advise me to keep it if the most likely use was for audio?

** Absolutely.

The 509B is a nifty little scope and a pleasure to use compared to a tedious, over complicated, fussy Rigol DSO.



When it finally died, I bought a Rigol DS1052E. And yes, there are a
few times when the pure digital system can mislead, but once you realise
what they are, the rest of the system performs very well indeed.
Admittedly I do far more digital stuff now, but I never found it was
fussy to set up, or gave false aliasing effects when used just for
poking around in analog systems. I guess the only thing I dislike is
having to switch the triggering from "auto" to "normal" via a menu. But
at least the triggering works well, unlike most of the old BWD scopes I
remember. Maby they improved that around the 70-80s, older ones were
hopeless.

** Never found that myself.

Audio testing and servicing is usually done with the aid of a signal generator - sine, square and other waveforms ( I use a differentiated square wave for some tests) and it is a simple matter to create a fixed level output from the generator and link that to the external sych input on a scope - DSO or analogue.

Triggering is then ROCK solid - despite any noise, distortion, oscillations or other nasty faults in the gear on test.

Doing this becomes essential when adjusting the null of a notch filter for THD testing - since the residual signal contains noise, harmonics of the test frequency and well as 50/100/150 Hz hum voltages.

FYI: To avoid hum loops in my test set up, there is a small audio transformer isolating the output from the generator from AC ground - it's response is near enough flat from 10Hz to 120kHz.


.... Phil

 

[Phil Allison]

Phil Allison wrote:

FYI: To avoid hum loops in my test set up, there is a small audio transformer isolating the output from the generator from AC ground - it's response is near enough flat from 10Hz to 120kHz.

** To be clear, the small tranny is in the fixed level (ie synch out) signal only.

... Phil

 

[Adrian Jansen]

On 30/11/2014 10:55 AM, Phil Allison wrote:

Gordon Levi wrote:

Phil Allison <pallison49@gmail.com> wrote:

Adrian Jansen wrote:

I know its fun to play with old gear, but realistically, you can buy
something like a modern Rigol scope for around $400 or so, and it will
work perfectly for troubleshooting on old audio circuits,


** Along with my BWD CROs I also own a Rigol DE1052E - $405 delivered from HK.

However, I found it near useless for service work on old or new audio electronics.

Why?


** Having grown up using analogue scopes, I am not happy to see stuff presented on the screen that simply is not there in the device under test. Gritty looking traces and the constant fear ofseeing artefacts like aliasing are a serious distraction - cos they closely resemble non existent faults.

I have also grown very accustomed to the image on the screen being presented in "real time" - so neither delayed in arriving or staying there after the signal has gone. The Rigol hangs on to the last screen for several seconds after the signal has stopped completely ruining the usual procedure for checking out noisy switches and connectors.

But maybe the worst thing is that while analogue scopse have constant bandwidth (like 50MHz) on all sweep ranges, DSOs do not. At typical audio he sweep speeds like 5mS per div the viewable bandwidth is barely the audio band. DSOs have real problems with displaying WIDE band signals correctly.

For example, a low frequency, fast square wave has invisible rises and falls on an analogue scope - not so on a DSO. You have to play with the sweep control to get any idea how fast the rise time is and hence the bandwidth of the circuit on test.


This thread reminded me that I have a BWD 509B that I never use
so I thought I would dispose of it and buy a digital scope in the
unlikely event that I felt the need to use a scope again. Would you
advise me to keep it if the most likely use was for audio?

** Absolutely.

The 509B is a nifty little scope and a pleasure to use compared to a tedious, over complicated, fussy Rigol DSO.



... Phil

Your mileage may vary.

As well as using many analog and digital scopes over the years, I owned
a Philips PM3350 combined analog and digital scope, which was probably
as good a combination as you could get. It also cost around $6000 in
the 1980s.

When it finally died, I bought a Rigol DS1052E. And yes, there are a
few times when the pure digital system can mislead, but once you realise
what they are, the rest of the system performs very well indeed.
Admittedly I do far more digital stuff now, but I never found it was
fussy to set up, or gave false aliasing effects when used just for
poking around in analog systems. I guess the only thing I dislike is
having to switch the triggering from "auto" to "normal" via a menu. But
at least the triggering works well, unlike most of the old BWD scopes I
remember. Maby they improved that around the 70-80s, older ones were
hopeless.

--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Note reply address is invalid, convert address above to machine form.

 

[Phil Allison]

Sylvia Else wrote:

This is a KIPOR GS2600.

** Hmmmmm....

A Chinese petrol powered, inverter / sine wave generator called KIPOR ?

So is " KIPOR " pronounced the same as kipper ??

In any case it sounds very fishy to me....

Easy to find reviews from unhappy customers on the net, some with a similar story but none with runaway petrol fires.



..... Phil

 

[Sylvia Else]

On 8/12/2014 12:16 AM, Phil Allison wrote:

Sylvia Else wrote:

This is a KIPOR GS2600.


** Hmmmmm....

A Chinese petrol powered, inverter / sine wave generator called KIPOR ?

So is " KIPOR " pronounced the same as kipper ??

In any case it sounds very fishy to me....

Easy to find reviews from unhappy customers on the net, some with a similar story but none with runaway petrol fires.

Trouble is, it seems easy to find reviews from unhappy customers for
practically any product. It's hard to form a view as to the overall
reliability or safety.

Sylvia.

 

[Phil Allison]

Sylvia Else wrote:

I was pondering the requirement for solar panel inverters to shut down
during an outage.

How exactly do they recognise an outage? The obvious answer is that the
voltage drops.

But how many solar power systems in a small suburban area does it take
to prevent the voltage from dropping low enough for the inverters to
disconnect?

** An enormous number I expect.

Could this explain why the voltage didn't vanish completely - for quite
a while, it remained high enough to energise the displays of some of my
appliances, which was confusing to say the least.

** If the sub station/local transformer breakers open on one or two phases, a load connected across the phases will tend to hold up the voltage on the open ones. 3 phase motors air conditioners would be the main examples in suburban areas.


..... Phil

 

[news13]

On Mon, 08 Dec 2014 11:36:49 +1100, Sylvia Else wrote:

I was pondering the requirement for solar panel inverters to shut down
during an outage.

How exactly do they recognise an outage? The obvious answer is that the
voltage drops.

But how many solar power systems in a small suburban area does it take
to prevent the voltage from dropping low enough for the inverters to
disconnect?

Umm, they generate AC within tight parameters and only those that stop
when the external voltage gets outside the tight parameters are allowed
to be installed in Australia.

The real problem is clowns who try to circumvent this.

 

[news13]

On Mon, 08 Dec 2014 12:55:37 +1100, F Murtz wrote:

Any way rung power mob who informed me they knew of a problem and it
would be working about nine thirty (aprox 3 hours time). It was back up
five minutes later, So apparently they just make up what ever time comes
into their heads

General guestimate time given out by person answering the telephone,
meanwhile tech is testing various legs and switching back on those that
test safe.

 

[news13]

On Fri, 12 Dec 2014 05:18:35 +1100, Rod Speed wrote:

That is just plain wrong too. There is MUCH less that can burn on the
outside of most houses, most obviously with brick and fibro houses and
small fires like that usually do burn themselves out without setting
fire to the house when they happen outside too.

Fibro = old = lots of fluff in cavities + well dried and decay = fire
spreads easily.

 

[news13]

On Thu, 11 Dec 2014 13:38:44 -0500, rickman wrote:


> You are just talking through your hat.

Rod doesn't wear a hat.

 

[Rod Speed]

news13 <newsthirteenspam-spam@woa.com.au> wrote

Rod Speed wrote

That is just plain wrong too. There is MUCH less that can burn on
the outside of most houses, most obviously with brick and fibro
houses and small fires like that usually do burn themselves out
without setting fire to the house when they happen outside too.

Fibro = old

Yep.

> = lots of fluff in cavities

Bullshit.

> + well dried and decay

Just another of your silly little fantasys.

> = fire spreads easily.

Just another of your silly little fantasys
with a small fire like that outside.

 

[Rod Speed]

pedro <me@privacy.net> wrote

Yep, just had it happen here. (For details of what and
how widespread it is, just google iphone4s and wifi).

Has anyone here any first-hand experience of getting Apple
to actually fess up and provide a replacement over this issue?

There doesn't appear to be anyone reading here anymore.

I've added a couple of groups that might get a response.

 

[Rod Speed]

pedro <me@privacy.net> wrote

Yep, just had it happen here. (For details of what and
how widespread it is, just google iphone4s and wifi).

Has anyone here any first-hand experience of getting Apple
to actually fess up and provide a replacement over this issue?

I wouldn't hold your breath, if the litigious yanks haven't
managed to fuck Apple over on that, no chance here.

 

[news13]

On Wed, 04 Feb 2015 18:41:53 +1100, Damian wrote:

Even with CCA reading, you need to punch in the claimed CCA rating to
get an accurate reading of the battery's current CCA reading.

CCA is a short term reading, the battery can provide it or not.

So, having to enter the claimed AH rating isn't an issue, as long as the
detected current AH rating is accurate enough.to assess the battery's
current capacity.

With Amp/Ht, the capacitry varies with discharge rates. commonly
batteries are listed at the 20 hour discharge capacity C/20, which
inflates the value. If your rate is C/5, then you won't get the same
output.

My idea of having this analyzer is indeed to get an accurate assessment
of used batteries.

You be better reading V(voltage) & s Hg(? specific Gravity) and
consulting some of the various chart for that particular brand/model
looking for a multi point match on one of the charts.

The load tester isn't an accurate way of doing that.
That because higher AH batteries usually pass the typical load tester
test, even though in reality it can be half dead already.

Most DD batteries give good Open Circuit voltage when they are freshly
charged, but allow them to sit for 24 hours and you get a truer reading.

One method is using a volt meter and an ammeter and just take periodic
readings as it discharges into a known load.

The other method is for when you can not sit there for hours, is to rig
up something like Voltage cut off that provides power to a known load and
timer. recharge at the end of each voltage cut off. Not as quick, but it
has the benefit that it is doing a more thorough test.

My 2c is that bottom line I want it to do something and the easiest way
is to set it to doing as close to that as I can and just observe the
result. I've never had much luck mixing various used batteries for heavy
loads. I just tend to dig deep and buy new stuff for critical needs like
the camp fridge/freezer and use unknowns for lighting, or powering the
lap top or old incaandescent flood lights.

 

[Damian]

"news13" <newsthirteenspam-spam@woa.com.au> wrote in message
news:masgdq$q67$2@dont-email.me...

On Wed, 04 Feb 2015 14:24:24 +1100, Damian wrote:

I'm just wondering whether any of you usenet monkeys have used the above
unit and whether you can recommend it?!!
I've tried to find some reviews on the internet, but can't find any
independent ones.
I'm after a battery analyzer that can do AH(amp hours) reading as
well(not just Cold Cranking Amps, etc)
Apparently the above model can do that.

How does it claim to do that?
All the stuff I've read about requires you to enter the claimed AmpHrs,
then do settings as you use it. Okay if you start with a new battery, but
chancy if trying to work with old one.

Even with CCA reading, you need to punch in the claimed CCA rating to get an
accurate reading of the battery's current CCA reading.
So, having to enter the claimed AH rating isn't an issue, as long as the
detected current AH rating is accurate enough.to assess the battery's
current capacity.
My idea of having this analyzer is indeed to get an accurate assessment of
used batteries.
The load tester isn't an accurate way of doing that.
That because higher AH batteries usually pass the typical load tester test,
even though in reality it can be half dead already.

 

[Damian]

"Gary R. Schmidt" <grschmidt@acm.org> wrote in message
news:c8s8qb-3h9.ln1@paranoia.mcleod-schmidt.id.au...

On 4/02/2015 2:16 PM, Damian wrote:
I've come across these two online stores based in mainland China.

http://www.carsets.co.uk/

http://www.aliexpress.com/

I've used aliexpress, and their parent alibaba, for some years, buying
electronic bits and pieces and car parts, and have had no problems with
them, but it is definitely caveat emptor, make sure that what you /think/
you are buying is what is being sold! Example: the use of the word
"chrome" does not necessarily mean the part is chromed steel.

I've also used Taobao via taobaofocus to get stuff from China, very cheap,
but again, you have to be sure of what you are ordering, very heavy on
Chinglish!

NFI about carsets.

Thanks. carsets.co.uk appears to be somewhat dodgy.
They say, if it sounds too good to be true, it usually ain't.
That may be the case with them.

 

[Jasen Betts]

On 2015-02-04, Damian <damian_andrews75@yahoo.com.au> wrote:

I've come across these two online stores based in mainland China.

http://www.carsets.co.uk/

http://www.aliexpress.com/

first one can work without having to open an account and email verification
and also works with paypal.
Second one need an account, like amazon & need account verification via
email, but doesn't work with paypal.

I'm pretty sure http://www.aliexpress.com/ is legit and has been around for
a while, but I'm not comfortable punching in credit card details into their
'secure' web page(doesn't work with paypal)
It's apparently a subsidiary http://www.alibaba.com/ which works for
retail+wholesale quick purchases. If that's the case, I'm not sure about the
reason for not supporting paypal!!!

having to pay paypal fees would increase costs. The fact that paypal
is owned by ebay may have something to do with it too.

http://www.carsets.co.uk/ supports paypal, but seems too easy overall and
can't find any reviews on internet about their legitimacy.
Even though it looks like a UK online shopping mall, it's actually based in
Beijing, China. It claims delivery via DHL in 3-5 working days, which sounds
too good to be true.

Element 14 manages overnight delivery from Australia to NZ cities
China to UK is only 20 or so hours further by air.

Their prices beat http://www.aliexpress.com/ by a good percentage.

Can you guys please advice me whether these two sites(especially
http://www.carsets.co.uk ) is legit or not?!

Aliexpress is legit, they do their own paypal style escrow - they hold
your money until you say you're satisfied, only then does the vendor
get paid. else you can get a refund.

--
umop apisdn