Axial Resistor, Fusing

[Yamaha5000]

Anyone know where these can be purchased?
Needing, all are 1/2w
3.9 Ohm
47 Ohm
68 Ohm
680 Ohm
220 Ohm

 

[raycarr00]

digikey, mouser, arrow....

 

[Yamaha5000]

digikey, mouser, arrow....

Mouser: No stock
Digikey: No stock
BD: No stock
Don't know the company Arrow, I will look

 

[spark1]

Looks like Mouser has metal films in at least some of those values. Maybe look at 1 watt versions, too, if space allows?

 

[Yamaha5000]

digikey, mouser, arrow....

No on Arrow

 

[Yamaha5000]

Looks like Mouser has metal films in at least some of those values. Maybe look at 1 watt versions, too, if space allows?

These are fused resistors, using 1w is not a good idea for circuit protection

 

[spark1]

I did not blow up the pic, so missed that they are fuse resistors.

 

[Yamaha5000]

This may very well be another find the needle in a hay stack.
KOA Speer does make these but no one stocks them and special orders are at a minimum of 5,000 qty and 6 months out.
If my memory serves me correctly, people are using metal film resistors at 1/2w. I just have a difficult time with that solution, maybe making this issue bigger than needed.

 

[raycarr00]

I just use regular film resistors to replace them with. some go with ptc fuses.

 

[Nashou66]

key term is flameproof

 

[Semanon]

So this is a good question and may solve the OP’s problem:

The engineers put a fusible resistor in place to protect the downstream components. However, the fusistors drift and cause other circuit problems, and I have never seen one act as a fuse.

Question: Is replacing a fusistor with a flameproof, film resistor of the same wattage a reasonable idea, or is it asking for trouble?

 

[raycarr00]

what about a 4 amp thermal fuse, breaker. or is it not the same as a fusistor but a ptc fuse? different components.

 

[spark1]

This may very well be another find the needle in a hay stack.
KOA Speer does make these but no one stocks them and special orders are at a minimum of 5,000 qty and 6 months out.
If my memory serves me correctly, people are using metal film resistors at 1/2w. I just have a difficult time with that solution, maybe making this issue bigger than needed.

It seems that replacing them with flameproof film resistors of same wattage is a fairly common practice...one employed by at least several of the well-respected techs here.

 

[raycarr00]

haven't seen a fusistor on a sansui burnt, yet. just a heck of a drift from spec. 1/3 w metal film is what I'm using in place of org.; others are doing the same. suppliers' backorders are some times overstated; might get them much sooner. mouser said 3-weeks, got them in about 3 days. on other orders, they said in stock, now they're saying backordered. projects on hold.