First off, you need to check the specs on the cable.
LMR is great stuff, 100% of the coax here is LMR but you need to read
the data sheet.
LMR195 and LMR200 are .195 nominal cables (high grade RG58 sized)
LMR240 is RG8X sized, .240 nominal...
0431173951 is .200 internal dia with a max cable size listed of .193...
Kinda tight even for a .195 cable...
0431164281 is .260 inner dia with a listed max cable size of .250
You also need to remember that the UltraFlex (-EF) versions of LMR have
a soft rubber jacket, not PVC...
The nominal listed diameter of -UF is same, but is actually larger...
This is fine for connectors (the jacket compresses) but for a solid
cylinder cable lube is needed, and the teeth on a clamp-on can bite
through the jacket. Need to go one size over to -UF
Now, that being said Jim is right, you need to go back to the PDF...
A bunch of 0431164281 would be great...If you were choking 2meters
Impedance is ~ 350ohms per at 150Mhz, use 10
For HF, you need turns, not a single pass
As Jim suggested, 0431173551 is a good clamp for
keyboard/mouse/usb/audio/wall-wart power/etc with a ~ .75 ID
Depending on the target freq 3 - 7 turns may be needed.
I have a full box of this part, with 2 - 3 on just about every wall-ward
or USB cable in the house.
For coax, LMR-240 is great and use stacks of the 2.4 inch toroids
(2631803802) or a large clamp-ons (0431177081) and follow Jims guide for
freq range/core/turns with rg8x sized cable.
My main feedline currently has
7 turns on 4 cores (LMR240 section in shack)
4 turns on 5 cores (LMR400)
Those are both at/near the shack end...
Far end has on 8x sized cable
5 turns 5 cores
4 turns on large clamp
6 turns on large clamp
This is for a inverted L res at ~ 4.2mhz with a SGC-235 autocouple at
the base used on 160M - 10M
On 6/17/14, 12:02 PM, Jorge Diez - CX6VM wrote:
> Thanks Jim!
>
> So finally I will use LMR-240-UF
>
> Will order round cable snap-its
>
> Seems that part number 0431164281 will be loose on the coaxial and will not
> be held near the connector
>
> Anyone tried part number 0431173951 with LMR-240-UF? Will close on this
> cable? Will be very bad if I buy a lot of them and then I see that don´t
> close.
>
> Thanks,
> Jorge
> CX6VM/CW5W
>
>
>
> -----Mensaje original-----
> De: Jim Brown [mailto:jim@audiosystemsgroup.com]
> Enviado el: martes, 17 de junio de 2014 01:22 p.m.
> Para: Jorge Diez - CX6VM; Rfi List
> Asunto: Re: [RFI] clamp on ferrites at Mouser
>
> On 6/17/2014 5:44 AM, Jorge Diez - CX6VM wrote:
>> What I understand is that the # 31 is good for frequencies below 5
>> MHz, but my question is what to put in internet modem cables,
>> transformer notebook, cable RS232 as don´t know where frequencies they
> are.
>
> We put chokes on these cables so that they will not radiate trash on our ham
> bands, so it is OUR frequencies that determine the chokes. For example, if
> we want to kill RF noise on 40 and 20M, we wind the chokes for those
> frequencies.
>
> 73, Jim K9YC
>
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>
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