bulb for HP 547A tracer

[Cooper]

Does anyone know what the bulb used in the HP 547A tracer, (and I
imagine in the pulser and probe also)The manual says it is 5 volt T1
size HP part no. 2140-0378 Illuminated Product Inc is the supplier and
the bulb is a "210". My question is wheather this is a 60ma bulb or a
20ma bulb.
Presently I have a 60 ma bulb installed, which makes the max current
draw from the tracer at 80ma, whereas the manual says less than 75ma
at 4.5 to 18 volts supply.The 60 ma unit seems to be an extra unneeded
load, since I would like to power it from preferably a 9v batt or 4
penlights for portability.
Thanks Dave

 

[Lizard Blizzard]

Cooper wrote:

Does anyone know what the bulb used in the HP 547A tracer, (and I
imagine in the pulser and probe also)The manual says it is 5 volt T1
size HP part no. 2140-0378 Illuminated Product Inc is the supplier and
the bulb is a "210". My question is wheather this is a 60ma bulb or a
20ma bulb.
Presently I have a 60 ma bulb installed, which makes the max current
draw from the tracer at 80ma, whereas the manual says less than 75ma
at 4.5 to 18 volts supply.The 60 ma unit seems to be an extra unneeded
load, since I would like to power it from preferably a 9v batt or 4
penlights for portability.
Thanks Dave

I think you ought to replace the bulb with a LED. They need a lot less
current to light up than a light bulb. And you will probably have to
put a resistor in series with the LED, to cut down on the max current.
If you do, then just use a value that reduces the current still further,
so your tracer will run longer off the battery.

But you should check to make sure that the LED won't make a change that
causes a problem somewhere else. It would be wise to look at the
schematic if you have access to it. Just to make sure. And you can use
the old light to hold the LED and resistor, if there's enough room.


--
----------------(from OED Mini-Dictionary)-----------------
PUNCTUATION - Apostrophe
Incorrect uses: (i) the apostrophe must not be used with a plural
where there is no possessive sense, as in ~tea's are served here~;
(ii) there is no such word as ~her's, our's, their's, your's~.

Confusions: it's = it is or it has (not 'belonging to it'); correct
uses are ~it's here~ (= it is here); ~it's gone~ (= it has gone);
but ~the dog wagged its tail~ (no apostrophe).
----------------(For the Apostrophe challenged)----------------
From a fully deputized officer of the Apostrophe Police!

<<Spammers use Weapons of Mass Distraction!>>

I bought some batteries, but they weren't included,
so I had to buy them again.
-- Steven Wright

FOR SALE: Nice parachute: never opened - used once.

F
o
d
d
e
r

f
o
r

s
t
u
p
i
d

n
o
t

e
n
o
u
g
h

i
n
c
l
d
u
d
e
d

t
e
x
t

e
r
r
o
r

m
s
g
..