On Apr 13, 2005, at 5:06 PM, Bob Maser wrote:
> McMaster/Carr sells electrical grade PTFE 1-1/2" rod for $35.04 per
> foot. I
> don't call that expensive.
Plastifab (818 967 9376) carries various diameters of G-10 tubing.
0.75" dia goes for around $1.20 a foot. G-10 is RF-friendly, does not
cold-flow like TFE, and it is easy to fabricate.
> Look up the material and many more on their
> website http://www.mcmaster.com/ I bought some Oil filled Nylon for a
> Hytower lookalike and they were quick to ship and their prices I
> thought
> were reasonable.
>
> Bob W6TR
> ----- Original Message -----
> From: "Harold B. Mandel" <ka1xo@juno.com>
> To: <francis.carcia@hs.utc.com>
> Cc: <philc@texascellnet.com>; <amps@contesting.com>
> Sent: Wednesday, April 13, 2005 6:08 PM
> Subject: [Amps] plate choke
>
>
>> Dear Francis,
>>
>> Here are some basic choices for coils.
>> The highlighted 24AWG coil on a 1.25" form seems
>> the most exciting choice. However, the 28AWG
>> will carry 640 mils, possibly, but I like to give it
>> plenty o'spare change.
>>
>> I've been winding chokes on 1" and 1.25" Teflon forms
>> in my machine shop for some commercial customers
>> for a while, now. The most orders I receive are for
>> devices on 1.25" forms, even though the Teflon is much
>> more expensive. Increasing the diameter does wonders to cut the
>> length of stock needed for a particular inductance, but
>> going from 1.25 to 1.5 inch Teflon stock is as much
>> of a wallet-nightmare as going from half-inch to two-inch
>> solid brass rod! 1.25 is then the most economical.
>>
>> Another option is the Ohmite L250J100 ceramic body
>> wirewound resistor. Those babies are wound with 26AWG
>> on a 3" ID ceramic core and have about 4.75" of windings.
>>
>>
>> 28AWG, 0.64Amp, (.75" form), 326Turns, 8.25" Long
>> (1.25"form), 133Turns, 3.35" Long
>>
>> 26AWG, 1.02.Amp, (.75" form), 402Turns, 12.81" Long
>> (1.25" form), 160 Turns, 5.8" Long
>>
>> 24AWG, 1.62Amp, (.75" form), 496 Turns, 19.96" Long
>> (1.25" form), 193 Turns, 8" Long
>>
>> 20AWG, 4.09Amp, (.75" form), 758 Turns, 48.5" Long
>> (1.25" form), 289 Turns, 18.5" Long
>>
>> 16AWG, 10.33 Amp, (.75" form), 1145 Turns, 116.4" Long
>> (1.25" form), 438 Turns, 44.5" Long
>>
>> '73,
>> Hal
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
Richard L. Measures, AG6K, 805.386.3734. www.somis.org
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|