Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: worth on November 27, 2011, 01:15:44 pm

Title: Is this right ??!!
Post by: worth on November 27, 2011, 01:15:44 pm
Trying to track down a power supply hum , when I noticed these 2K cement resistors. They appear to have "grown together". Is this a specialized resistor of some sort ? I haven't seen one like this before.
Title: Re: Is this right ??!!
Post by: kagliostro on November 27, 2011, 01:29:39 pm
Quote
Is this a specialized resistor of some sort ?

I'm prone to think so

you can also observe it and look to the printed data

if only one is labeled is easy that is a "double" resistor

what about the other side of the moon (resistor) ?

are there 2 connection, 1 connection, or none ?

Kagliostro
Title: Re: Is this right ??!!
Post by: worth on November 27, 2011, 01:37:17 pm
Each resistor  says " Mexico 2K 10%" and both have 2 axial leads , like an ordinary cement power resistor.
Title: Re: Is this right ??!!
Post by: bigsbybender on November 27, 2011, 02:00:51 pm
They are just two resistors that have grown together. That filler stuff must have gotten soft by either heat or atmospheric conditions.


j.
Title: Re: Is this right ??!!
Post by: worth on November 27, 2011, 02:02:15 pm
Yes.. but is it a problem ?
Title: Re: Is this right ??!!
Post by: bluesbear on November 27, 2011, 03:42:24 pm
Those things are cheap! I'd spend the few cents just to be sure.
Dave
Title: Re: Is this right ??!!
Post by: eleventeen on November 27, 2011, 04:08:56 pm
It was somewhat common in early transistordom to have two small-signal transistors clipped together on one heat sink so that they would remain at the same temperature level.

I have never seen it with resistors.
Title: Re: Is this right ??!!
Post by: bigsbybender on November 27, 2011, 06:53:06 pm
Yes.. but is it a problem ?

Do they read correctly on the meter?  If they are on the verge of burning up, then the values tend to drift.

It's not likely for these two resistors to have become conductive to one another, as that material is probably rated for 600v+.


j.
Title: Re: Is this right ??!!
Post by: worth on November 27, 2011, 08:25:30 pm
One resistor reads correctly EVENTUALLY. On one,  the meter reading starts low , then climbs slowly up to around 2K.. not like the usual resistor. On the other , the reading is way off.
Title: Re: Is this right ??!!
Post by: jojokeo on November 27, 2011, 08:42:12 pm
One resistor reads correctly EVENTUALLY. On one,  the meter reading starts low , then climbs slowly up to around 2K.. not like the usual resistor. On the other , the reading is way off.

You need to lift one of their end(s) and measure out of circuit.
Title: Re: Is this right ??!!
Post by: DummyLoad on November 27, 2011, 08:44:42 pm
One resistor reads correctly EVENTUALLY. On one,  the meter reading starts low , then climbs slowly up to around 2K.. not like the usual resistor. On the other , the reading is way off.

you need to lift one end of each out of circuit to read them accurately - it seems as though one has a cap tied to one end and the other has other stuff in parallel. "it" looks to be 2 parts.

--DL