Have another Cantenna question

[Multi-Volti]

These are definitely for RF, but it was the non-inductive wirewounds I was
disparaging for RF.

I think these are relatively costly compared to wirewound, but don't know
for sure.

I think but am not sure the Heath Cantenna one is 30 W.

I had heard those resistors don't like overheating, but 350 C doesn't sure
frail.

Oh, well.

Maybe the website refers to website and distribution.

Another alternative that would require ingenuity would be Caddock or EBG
power film resistors. Dale might make some too. For example, Caddock has a
50W TO-220 resistor that I think is good to 500 MHz.

Now, TO-220 dissipating 50W means it needs some serious heatsinking. Maybe a
fat finned heatsink dropped into the oil would suffice, if the old resistor
simply sat in the oil...it does have larger surface area to conduct the heat
to the oil.

Caddock I think will sell direct, but there might be a minimum order, and
maybe 50 ohms is standard enough to hope some exist already.

Murray

----- Original Message -----
From: Neil Morrison <neilsmorr at HOTMAIL.COM>
To: <HEATH at LISTSERV.TEMPE.GOV>
Sent: Friday, October 18, 2002 8:55 PM
Subject: Re: Have another Cantenna question


> This is their blurb:-
>
> "Type SP Resistors"
> "With ceramic material operating temperature of 350°C, Type SP
> resistors provide great non-inductive power handling capacity - at
> frequencies into the GHz range."
>
> I see this too:-
>
> Type: 886SP
> Dim: 5" x 3/4"
> Ohms: 1.0 to 330
> Watts to: 90
> Peak Joules: 500
> Peak Volts: 4,000
>
> Haven't a clue about price though. What was the spec on the Cantenna?
>
> Neil
>
> ----- Original Message -----
> From: "Multi-Volti" <murray at multi-volti.com>
>
>
> > Globar/Cesiwyg definitely makes the right kinda resistor.
> >
> > There are 'non-inductive' wirewounds, but they just reduce the
> inductance
> > with reversed winding direction. They offer improved impedance for
> > applications where you still need the power dissipation, transient
> > capability and reliability of wire wound construction, but it still
> probably
> > isn't good enuff for RF. I think it probably works out to 10's or
> low 100's
> > of kHz. (Guessing)
> >
> > Murray
>
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