[K3] MFJ-1786 Antenna

[VK7JB]

Hi Dave,

I've used an MFJ 1786 for some years now and my experience has been positive. It's not a beam at 100ft, but over many hundreds of QSOs,  the reports I've received and sent compare favorably with a wire doublet up at 40 feet. There's a learning curve associated with tuning it, but once you have the knack, it's very quick. Yes, the bandwidth is VERY narrow and you must get the loop precisely tuned to work anyone. You can't get it nearly to resonance and then force feed the part-tuned loop with an external tuner.

I've worked a lot of QRP DX with my MFJ 1786. It's fun and very compact.

73,
John
VK7JB
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Jeff Herr]

I just updated to 1.32 firmware and the release notes displayed from the
utilities help menu are not updated.



______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Jeff Herr]

....50 ohm non reactive 1/4 watt axial lead resistor maybe 1% or better.

I have a couple of old amphenol bnc 240 ohm terminators that I want to
repurpose to 50 ohm.

I am having trouble finding a non reactive part thats good up thru 500mhz.



Jeff Herr,  WW6L
4636 Kelton Way
Sacramento, Ca 95838
916.925.6089



______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Elecraft mailing list]

Hi Jeff,

Depending on the connector used, and the frequency of interest, I found the Caddock 1/4 W precision film resistors to be good to about 300 MHz,  Try, RN55D49R9F.  (49.9 ohm 1%) .  Allied carries them.

Mel, K6KBE



On Saturday, September 13, 2014 12:49 PM, Jeff Herr <[hidden email]> wrote:
 


....50 ohm non reactive 1/4 watt axial lead resistor maybe 1% or better.

I have a couple of old amphenol bnc 240 ohm terminators that I want to
repurpose to 50 ohm.

I am having trouble finding a non reactive part thats good up thru 500mhz.



Jeff Herr,  WW6L
4636 Kelton Way
Sacramento, Ca 95838
916.925.6089



______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Don Wilhelm-4]

I would also suggest that the Caddock 50 ohm 915 series power film
resistors be considered.
Although these are rated at 15 watts with a heatsink, they are rated for
1.25 watts in free air.
Mounted to the BNC connector with zero length leads, they should be good
up to 500 MHz.
See http://www.caddock.com/Online_catalog/Mrktg_Lit/MP9000_Series.pdf

I use the higher power ratings (on a heatsink) for dummy loads, and they
can be considered 'precision dummy loads' with a 1% tolerance and the
top frequency depends on the lead length and other mounting
considerations.  150 MHz is practical with little consideration for lead
length.

Warning - do not exceed the power ratings or they will 'let the smoke
out' quickly.

73,
Don W3FPR

On 9/13/2014 7:17 PM, Mel Farrer via Elecraft wrote:

> Hi Jeff,
>
> Depending on the connector used, and the frequency of interest, I found the Caddock 1/4 W precision film resistors to be good to about 300 MHz,  Try, RN55D49R9F.  (49.9 ohm 1%) .  Allied carries them.
>
> Mel, K6KBE
>
>
>
> On Saturday, September 13, 2014 12:49 PM, Jeff Herr <[hidden email]> wrote:
>  
>
>
> ....50 ohm non reactive 1/4 watt axial lead resistor maybe 1% or better.
>
> I have a couple of old amphenol bnc 240 ohm terminators that I want to
> repurpose to 50 ohm.
>
> I am having trouble finding a non reactive part thats good up thru 500mhz.
>
>
>
> Jeff Herr,  WW6L
> 4636 Kelton Way
> Sacramento, Ca 95838
> 916.925.6089
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Fred Townsend-2]

Jeff I doubt you will find any axial leaded part that is good to 500 MHz because the package inductance will roll off response below 500 MHz. However if you insist on axial leaded there are any number of 50.1 ohm metal film, axial leaded  parts available from Digikey www.digikey.com. Also Ohmite makes a 50.0 ohm, 50 watt resistor, NI, in a to220 case that is pretty good. Also available from Digikey. You can look up your own part numbers with their online finder.

73
Fred

-----Original Message-----

>From: Jeff Herr <[hidden email]>
>Sent: Sep 13, 2014 3:47 PM
>To: [hidden email]
>Subject: [Elecraft] OT looking for a part number for a....
>
>....50 ohm non reactive 1/4 watt axial lead resistor maybe 1% or better.
>
>I have a couple of old amphenol bnc 240 ohm terminators that I want to
>repurpose to 50 ohm.
>
>I am having trouble finding a non reactive part thats good up thru 500mhz.
>
>
>
>Jeff Herr,  WW6L
>4636 Kelton Way
>Sacramento, Ca 95838
>916.925.6089
>
>
>
>______________________________________________________________
>Elecraft mailing list
>Home: http://mailman.qth.net/mailman/listinfo/elecraft
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:[hidden email]
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html
>Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]