Calling Electronic gurus....

scargill

i'm replacing a burnt out resistor on a HP 1220c.
I need a 1/2 watt 15k ohm resistor. They cost around 10c each - so the hassle of going to Peats to buy one isn't really worth it.

Would someone here happen to have one (or two) that they could post to me please !!

printer is in bit of a mess on the desk and I'm getting a hard time about it - so I'd appreciate it !!


(article I'm following in attempt to fix printer: here)

edit: this might be better in Sci > Engineering ? if no replies mod can delete/move.

doud

hey scargill,

sorry, I don't have any resistors to send, you can unsolder one from some old dead device if you have anything lying around. [STRIKE]And think about it : resitors don't blow up out of the blue for no reason, you maybe be facing a bigger issue with the power stage not regulating anymore or you might also have a short circuit some where. Find out the cause of this blown resistor if you can before changing it, as you might just be witnessing another one fuse when you power the hp 1220 back.[/STRIKE]

DouD

scargill

the blown resistor is caused by glue on a toroid that melts and covers the resistor causing it to overheat. It appears to be a common fault on the 1220c.

Gurgle

5.77mA is the max current you can run through a 0.5W 15K resistor.
Thats not a terribly large amount for a PSU.

But its not something that will be in most electronic gadgets, .25W or .125W are more common.

Or to put it another way, I don't have any.

Michael Collins

Don't have any 1/2 Watt ones I'm afraid but I could offer you two 33k 1/4 Watt resistors, if there's room on the PCB for them. Then obviously in parellel you have 33k||33k = 16.5k

scargill

Thanks M.C. - first time I've played around with this - what do you mean by parallel ? If you reckon this will do the same job as the the resistor I'm looking for I'd appreciate getting them from you.

copacetic

what footprint do you need?
parallel is connecting both to the same 2 points.

if they are through hole (i.e old) you put both resistors through
same holes, if they are surface mount, you just piggyback them.

Gurgle

scargill wrote:

- what do you mean by parallel ?

Should you really be messing around with a PSU ?

scargill

Gurgle wrote:

Should you really be messing around with a PSU ?

LOL - I'll be careful mammy