8V 40mA bi-pin lamp (Marantz)

[jfeng@my-deja.com]

On Friday, September 6, 2013 1:39:08 PM UTC-7, Trevor Wilson wrote:

**Except that is a REALLY dumb idea. The dial scale in the old Marantz
recievers is blue.

Maybe, maybe not. If I had one in my inventory/junque box, I would consider it a cheeap expeeriment and give it a try. If I could get one for about a dollar, I would consider taking a chance. You may have a differnt tolerance for taking this kind of risk.

 

[dave]

On 09/06/2013 05:35 AM, Phil Allison wrote:

"dave"


If you see "flicker" at 30 Hz you must hate television.


** Huh ???

The refresh rate of CRT based TVs is at least 50Hz - because of
interlaced scanning.

There is still massive strobing if you wave an object in front of one, as
the dots / stripes go dark long before the next refresh cycle.

A LED ( any colour ) pulsed at 30Hz flickers obviously - this stops at
about 40 to 45 Hz.


... Phil

TVs today go down to 24 FPS progressive.

 

[Trevor Wilson]

On 7/09/2013 5:41 AM, jfeng@my-deja.com wrote:

On Friday, September 6, 2013 6:29:13 AM UTC-7, Tim Schwartz wrote:

There are the source indicators (PHONO, FM, AM, TAPE, AUX, ....)
NOT the dial scale lamps, which are 'fuse type'.

--Tim

I guess I never had to replace any of those in my sets.....;-)

I hesitate to enter the fray, but if I thought 12V lamps were brigth
enough, I would just use those. That might be easier to find.
Operating at 8V, they would probably last a very long time (the GE
rule of thumb from the middle of the last century was the twelfth
power of the voltage).

**Except that is a REALLY dumb idea. The dial scale in the old Marantz
recievers is blue. Incandescent lamps emit very little energy in the
blue end of the spectrum (which is why Marantz had to use large numbers
of lamps in the first place - Technics and Pioneer models of the time
managed to use two or three lamps, whilst Marantz employed as many as
9). Operating an IC lamp at reduced Voltage will reduce blue output
still further, thus causing the dial scale to be quite dark and possibly
unusable. Blue LEDs are the perfect solution. Indefinite life-span, low
heat dissipation and perfect colour rendition. White LEDs are also
excellent, but with a shorter life-span and sligtly inferior colour
rendition.

--
Trevor Wilson www.rageaudio.com.au

 

[Trevor Wilson]

On 7/09/2013 7:53 AM, jfeng@my-deja.com wrote:

On Friday, September 6, 2013 1:39:08 PM UTC-7, Trevor Wilson wrote:

**Except that is a REALLY dumb idea. The dial scale in the old
Marantz recievers is blue.

Maybe, maybe not. If I had one in my inventory/junque box, I would
consider it a cheeap expeeriment and give it a try. If I could get
one for about a dollar, I would consider taking a chance. You may
have a differnt tolerance for taking this kind of risk.

**It's not a risk. It's just a dumb idea that won't provide any
worthwhile benefit.


--
Trevor Wilson www.rageaudio.com.au

 

[Phil Allison]

"dave"
Phil Allison wrote:

"dave"


If you see "flicker" at 30 Hz you must hate television.


** Huh ???

The refresh rate of CRT based TVs is at least 50Hz - because of
interlaced scanning.

There is still massive strobing if you wave an object in front of one, as
the dots / stripes go dark long before the next refresh cycle.

A LED ( any colour ) pulsed at 30Hz flickers obviously - this stops at
about 40 to 45 Hz.


TVs today go down to 24 FPS progressive.

** Completely irrelevant.

Wot a dumbass.


..... Phil

 

[Phil Allison]

<jfeng@my-deja.com>

**Except that is a REALLY dumb idea. The dial scale in the old Marantz
recievers is blue.

Maybe, maybe not. If I had one in my inventory/junque box, I would consider
it a cheeap expeeriment and give it a try. If I could get one for about a
dollar, I would consider taking a chance.

** Wide angle, 5mm blue LEDs sell for about $1.00 each.

The correct 8V bi-pin lamps will cost you more.

You will need one resistor ( 470 ohms to 1kohms) for each LED and just
ignore the insane crap here from AD etc about visible flicker at 60Hz.


.... Phil

 

[Arfa Daily]

"Black Iccy" <Daedelus@whereamIinvalid.com> wrote in message
news:tnei29h3c7vtduv106ee9p6icdolkteus7@4ax.com...

On Fri, 6 Sep 2013 01:31:39 +0100, "Arfa Daily" <arfa.daily@ntlworld.com
wrote:

That aspect can be mitigated by
having a conventional diode in inverse parallel, but this will result in a
flicker at half the supply frequency that Phil can't see, but some of us
can, or by putting another LED in inverse parallel, which will conduct on
the opposite half cycle producing light, and clamping the reverse voltage
across the first diode to the value of the forward voltage of the second
diode, different, of course for different colours.

Surely, it will be at the _SAME_ frequency but exist as a light
source for only half the period (duty cycle). N'est-ce pas?

Each LED will flicker at half the supply frequency, but each will emit light
on opposite halves of the AC waveform. Thus, if the two LEDs are physically
close together, the flicker from each will be mitigated by the other.

Arfa

 

[Arfa Daily]

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:b8t95nF7ovrU1@mid.individual.net...

"Arfa FUCKWIT Daily"
"Phil Allison"


** LEDs are, believe it or not, DIODES !!

So they can be used on low voltage ( ie 6.3V ) AC supplies with only a
series resistor.


Yes. However, they are not renowned for having a very high PIV, so
whilst you would probably get away with just a series resistor at low
AC,


** Jesus FUCKING CHRIST -

this IDIOT just DOES NOT READ !!!!!!!!!



No, it's YOU who either does not read,


** FFS - you REPEATED the info in MY post back to me !!!

You pompous, bullshitting, fucking nut case.

Back at you on that one ! If *I'm* a nutcase, fuck knows what that makes you
....

.... Phil

Give it up Philip. You should have learnt by now that you never end up
beating me down like you do most people, because I simply don't care what
you think or say about me. You behave on here like a total twat. Everybody -
not just me - thinks so, but you just don't see it do you ? You try to come
across as though you know everything about everything, and while sometimes
you appear to be quite clever when you've got your right head on, most of
the time, all you do is latch onto some irrelevant point and labour and
labour and labour it, getting ever more and more angry and stupid about it.
You are, quite simply, mentally ill, which is why most of the time, I'm
prepared to let you get on with it.

So, have you had enough yet, and ready to get back under your rock, or shall
I keep beating up on you ... ?

Arfa

 

[Phil Allison]

"Arfa Fuckwit Daily"
"Black Iccy"

"Arfa Fuckwit Daily"

That aspect can be mitigated by
having a conventional diode in inverse parallel, but this will result in
a
flicker at half the supply frequency that Phil can't see, but some of us
can, or by putting another LED in inverse parallel, which will conduct on
the opposite half cycle producing light, and clamping the reverse voltage
across the first diode to the value of the forward voltage of the second
diode, different, of course for different colours.

Surely, it will be at the _SAME_ frequency but exist as a light
source for only half the period (duty cycle). N'est-ce pas?


Each LED will flicker at half the supply frequency,

** FFS - wake up you IMBECILE !!!!!!!!!!

Half wave rectification = 50 /60 Hz ripple.

Full wave = 100 /120 Hz ripple.

Dead horses are lining up in drives right now ...



..... Phil

 

[William Sommerwerck]

"Arfa Daily" wrote in message news:2AvWt.74113$M%4.29548@fx29.am4...

You are, quite simply, mentally ill, which is why most of the time,
I'm prepared to let you get on with it.

One of the things I learned in screenwriting school was that it makes no sense
to tell stories about good versus evil -- specifically, stories about a
person's internal conflict over good and evil. The reason is that human beings
always think that whatever they do is good -- or at least, not wrong.

Regardless of /why/ Phil jumps so abruptly between Dr Jekyll and Mr Hyde, both
perspectives seem right /to him/. And no amount of rationality or arguing will
enable him to see any differently.

Similarly, when a person in another group who'd repeatedly abused me and
others, in the nastiest manner possible, said that he'd been only teasing
me -- and why didn't I take it in good humor? -- it became obvious that
(whether or not he's "disturbed") he could not step outside his perceptions
and recognize that his behavior was beyond the pale.

 

[Phil Allison]

"William Sommerwerck"

> Regardless of /why/ Phil jumps so abruptly between Dr Jekyll and Mr Hyde,

** No such thing is going on, at all.

AD is mentally defective, in about 5 ways at once.

He cannot be reasoned with as he is TOTALLY unaware of any of his defects.
He posts utter crap all the time and does not even read the corrections -
his bloated ego blinds him to the value of them.

Usenet is completely infested with people like AD, they cannot be persuaded
to leave and no amount of " outing " or verbal abuse has any effect.

In the real world, it is easy enough to avoid the likes of AD ( unless he is
your boss or teacher ) - but usenet provides no way of dealing with them.

Big mistake in how the scheme was first set up.

Apparently, Facebook and Twitter is not much better.



.... Phil

 

[Phil Allison]

"Arfa FUCKWIT Daily"

** LEDs are, believe it or not, DIODES !!

So they can be used on low voltage ( ie 6.3V ) AC supplies with only a
series resistor.


Yes. However, they are not renowned for having a very high PIV, so
whilst you would probably get away with just a series resistor at low
AC,


** Jesus FUCKING CHRIST -

this IDIOT just DOES NOT READ !!!!!!!!!


No, it's YOU who either does not read,

** FFS - you REPEATED the info in MY post back to me !!!

You pompous, bullshitting, fucking nut case.




..... Phil

 

[Black Iccy]

On Sat, 7 Sep 2013 02:50:22 +0100, "Arfa Daily" <arfa.daily@ntlworld.com>
wrote:

That aspect can be mitigated by
having a conventional diode in inverse parallel, but this will result in a
flicker at half the supply frequency that Phil can't see, but some of us
can, or by putting another LED in inverse parallel, which will conduct on
the opposite half cycle producing light, and clamping the reverse voltage
across the first diode to the value of the forward voltage of the second
diode, different, of course for different colours.

Surely, it will be at the _SAME_ frequency but exist as a light
source for only half the period (duty cycle). N'est-ce pas?


Each LED will flicker at half the supply frequency, but each will emit light
on opposite halves of the AC waveform. Thus, if the two LEDs are physically
close together, the flicker from each will be mitigated by the other.

Arfa

This whole argument is silly but, pardon me, that is NOT what you said Arfa
(thus my reason for jumping in) and you appear to be combining two distinct
posts.

Message-ID: <mf%Vt.37541$Wl2.28334@fx04.am4>

That said, if two LEDs are used in inverse parallel as you suggested, rather
than paralleling with a conventional diode or just relying on the reverse
blocking of the LED, flicker is not an issue, as each LED will produce light
on opposite half cycles.

If this (back-to-back) is done, the "flash" frequency (periodic rate if you
prefer) will be 100 times / sec. Correct? Two flashes per complete sine?
Still only 1 flash per each diode per full cycle of course but most certainly
flash pulsing will not be halved under any conditions. Doubled in fact.

And just for kickers, the forward conduction breakdown from each diode, in
turn, ought to be lower than the reverse destruction breakdown voltage, in my
experience anyway. Therefore a single dropping resistor would be effective.

But at a later post, Message-ID: <Mn9Wt.58225$AH1.45199@fx19.am4> in full...

Which is exactly what I said. If running them on AC, they are fine as long
as the series resistor is of sufficient value to limit the forward current,
and the reverse voltage on the opposite half cycle does not exceed the
rather low PIV that LEDs tend to have.
So far so good

That aspect can be mitigated by
having a conventional diode in inverse parallel, but this will result in a
flicker at half the supply frequency that Phil can't see, but some of us
can, or by putting another LED in inverse parallel, which will conduct on
the opposite half cycle producing light, and clamping the reverse voltage
across the first diode to the value of the forward voltage of the second
diode, different, of course for different colours.

Now what do you mean by that? Piggying a standard .6 V drop diode across
a dual, reversed set? That would circumvent 1 of the diodes getting a
sufficiently high forward voltage bias. In that case, we are back to half-wave
operation at the line frequency (whatever that may be). BUT, it (the flashes)
will never be at half the line frequency (which Phil defines as the repetition
rate).

OR do you mean having ...

Just a single LED with conduction in a particular direction but which is being
shunted by a reverse diode so that the LED's being protected from reverse
over-voltage? If so, then the same conditions as just outlined, still apply.

But, whichever viewpoint you deem more accurate/intended, indeed even if you
reject both, I repeat the section of your post for emphasis ....

That aspect can be mitigated by
having a conventional diode in inverse parallel, but this will result in a
flicker at half the supply frequency that Phil can't see, but some of us
^^^^^^^^^^^^^^^

No sir. Never *half* the supply frequency. That would mean 25 or 30 pulses/sec
for standard 50~ or 60~ supplies. Power might well not be consumed for the
full input cycle - a fact which we acknowledge by using the term 'duty factor'
or 'duty cycle'. Irrelevant what Phil sees -)

Reducing to absurdity: A simple transformer fed from a 50~ source with a
secondary output sufficient to produce forward conduction will produce 50
flashes/sec. Not half. Not 25. Now, if we'd full-wave rectified, we'd get 100
FPS from a single diode.
I'm outa here.

 

[Phil Allison]

"Black Iccy"

And just for kickers, the forward conduction breakdown from each diode, in
turn, ought to be lower than the reverse destruction breakdown voltage, in
my
experience anyway. Therefore a single dropping resistor would be
effective.

** For interest sake, I checked a few 5mm white LEDs in stock for reverse
breakdown.

Each exceeded 21 volts with reverse current under 3uA ( maybe nothing)

Be fine with a 12.6V AC heater supply and ONE resistor.

There is NO flicker.


.... Phil

 

[Ian Field]

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:ZVQVt.28602$99.10031@fx24.am4...

"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:b8pgpbFeir5U1@mid.individual.net...
On 4/09/2013 11:52 PM, Tim Schwartz wrote:
Hello all,

Anyone know of a generic lamp that is an 8 volt, 40 mA bipin type?
These are used as source indicators in receivers like the Marantz 2270
and 2275. The 6.3 volt 7380 is readily available, but won't last long
running on 8 volts, and gets too hot as well.

Of course a reliable vendor who sells them would be just as good.

Many thanks,
Tim Schwartz
Bristol Electronics

**I've found that owners of those old Marantz recievers are only too
happy to spend some extra bucks on replacing ALL lamps with LEDs. That
includes the stereo and source indicator lamps. The payoffs are huge.
They include:

* Far lower power consumption and consequent minimised damage to the
plastic housing that contains the dial back-lighting.
* Far, far more attractive dial lighting, if the LEDs used are blue ones.
* Indefinite (or at least very long) life-span for the lighting.

I've found that Lumileds™ work extremely well, due to their wide
dispersion characteristics. It requires some extra effort for the
repairer though. You can purchase plug-n-play replacements from eBay, if
you can't be bothered doing your own work.

--
Trevor Wilson www.rageaudio.com.au


Although of course, care needs to be taken that the lamps are actually
being fed with DC. In many items using pea bulb indicators and back
illumination, they are fed with AC straight off the tranny, or sometimes
via a series resistor whether AC or DC. This means that if you drop the
current by swapping to LEDs, the voltage will rise. I have also found that
it is hard to match the 'colour' of small bulbs with LEDs, particularly
when they are deliberately under-run to produce a more 'lemon' coloured
light. Things like tuning meters just don't look right if the light behind
them is too white. And even with wide angle LEDs, the light dispersion is
sometimes not enough to 'fill' an area with light, resulting in uneven
illumination.

Last time I ordered wide angle IRLEDS, what arrived had nearly flat lens
end - filing down has appeared in various forums recently, but last time I
tried that, I hit the bond wire!

Flattening the end a bit with a coarse abrasive also makes it a diffused
light source.

Cheapo headband lamps or 24 LED worklights are a good source of LEDs so
cheap you can afford to lose a few experimenting.

 

[Ian Field]

"Leif Neland" <leif@neland.dk> wrote in message
news:mn.2a337dd9ab7f140a.130671@neland.dk...

Phil Allison kom med fřlgende:
"Arfa Daily"

Although of course, care needs to be taken that the lamps are actually
being fed with DC.


** LEDs are, believe it or not, DIODES !!

Having LEDs run on one half-phase of AC can cause flicker.

More importantly, you have to protect it on the alternate half-cycles, the
series resistor doesn't usually drop enough voltage at the reverse leakage
current to protect the typically 5V PIV.

Either use the LEDs in inverse-parallel pairs, or protect each one with an
inverse-parallel 1N4148.

 

[Ian Field]

"Gareth Magennis" <sound.service@btconnect.com> wrote in message
news:ddWdnUGBWs9RHrXPnZ2dnUVZ8mCdnZ2d@bt.com...

** For typical red bezels or indicator lights, it is simply not visible.


It is to some of us. I find the PWM'd LED flicker of road works cone-top
beacons very annoying, as well as the flicker from PWM'd LED stop and
tail lights on some makes of car. My wife doesn't notice it all, however.
Admittedly, the effect is worse at the periphery of vision, but I still
see it looking head on at the source.



Although I don't find this particularly annoying, I very much notice it
too.
For me the effect manifests itself as a line of bright strobing when my
eyes move horizontally past the flickering LED's. Like * * * * *
* * * * * * *

Inspired by novelty neon plug-caps, I once wired a PL type florescent tube
in series with the HT lead on a motorcycle, a cop gave me a really funny
look - but was too lazy to turn round and chase after me.

The ignition became unreliable about a month later so the experiment wasn't
repeated.

 

[Ian Field]

"Mike Tomlinson" <mike@jasper.org.uk> wrote in message
news:1jVOMOOXdWKSFwmY@jasper.org.uk...

En el artículo <mn.31b07dd9e5677419.130671@neland.dk>, Leif Neland
leif@neland.dk> escribió:

The treatment could be botox at the vocal cords (would it help for
typing? Possibly in the hands instead) or brain surgery.

He'd have to have a brain in the first place to operate on.

And yet he still has more lucid moments than JF & JT put together!

 

[Ian Field]

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:b9027vFpe5eU1@mid.individual.net...

"Black Iccy"


And just for kickers, the forward conduction breakdown from each diode,
in
turn, ought to be lower than the reverse destruction breakdown voltage,
in my
experience anyway. Therefore a single dropping resistor would be
effective.

** For interest sake, I checked a few 5mm white LEDs in stock for reverse
breakdown.

Each exceeded 21 volts with reverse current under 3uA ( maybe nothing)

You might have got away with dumping that much reverse voltage just the one
time, but continuous reverse half cycles probably puts their life expectancy
in the same ball park as filament bulbs!

 

[Gareth Magennis]

It is to some of us. I find the PWM'd LED flicker of road works cone-top
beacons very annoying, as well as the flicker from PWM'd LED stop and tail
lights on some makes of car.




There's an app note here for a Stop/Tail IC.

http://www.maximintegrated.com/app-notes/index.mvp/id/4316
(It claims an operating frequency of 200 Hz, but this is not necessarily
what is currently out there)


Seems a bit Sledgehammer To Crack a Nut to me, but there you go.
My current Stop and Tail technology is 2 wires and a cheap easily
replaceable dual filament bulb.




Gareth.