[Elecraft] Open Wire Feed Line Arrestor
Still running my K1 (#1423) on inefficient low antennas. I have some trees that will give me good height 50-60' and orient the main lobe of a double extended zepp (14MHz) toward Oregon, take notice ECN. I have come across a device that will keep the antenna at near DC ground at all times. http://www.arraysolutions.com/Products/ice/impulse1.html go down to "Open Wire Arrestor", Model 309 "All units use torroidal inductors and present near dead DC short on antenna side of arrestor, constantly draining feedline wires of static and any developed voltage potential feedthrough breakdown voltage from input ports to output ports 4,000 to 6,000 volts. Arrestor units may be placed anywhere in the feedline at ground level without serious change in tuning, but small change may be detectable due "to small" increase in total feedline length caused by size of arrestor case & circuit." Just wondering if anyone else has used this or a similar item and what comments might be made. Just trying to be save from lightning. I would also put a DPDT knife switch between the feed line and the K1 with BL2 to ground the feed line when not in use. Thanks all. 73, W1TF, Ty in GA __ Yahoo! DSL Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Open Wire Feed Line Arrestor
Hi Ty, I had some minor damage to my K2 from ESD in 2004. I didn't have any form of lightning protection at the time. I did purchase this device and haven't had any problems since. Of course, maybe I haven't had a nearby discharge, but didn't want to risk it again. My new shack has this installed as well. Mine are both installed closer to the rig (on the output side of my inside antenna switch). I've opened one of these up, and suspect you could easily build one for a fraction of a commercial unit. For my new installation, I've buried all of my feedlines (longest run is about 80'). This has a twofold effect, lightning protection and common mode attenuation. OK, four benefits, all the lines are out of sight and harm's way. The work is not as hard as it sounds. I used a little Honda rototiller to dig the trench. Then got PVC sprinkler line (I've used both the black coiled stuff and 20' lengths, size depends on what you're trying to run thru it.) and buried it. You can bury some lines directly, but it makes repair/replacement a real headache. I run heliax/coax, rotor control and switching cables thru them. Also, I lay a ground wire in the trench on the bottom and tie all my ground rods together. Hope this helps. Cheers, Julius n2wn ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Open Wire Feed Line Arrestor Conclusion
Thanks to AC7AC, F5LCI, GM4ESD, K5VH, N2WN, W6FB, WB1DOG. For their comments on and off the reflector. I have changed my antenna from about 6 m of wire draped inside over a window frame and ground being the ground in an AC outlet, to an 26.8 m wire at 12 m high, center fed with 450 Ohm line. What a difference! Eznec says I have picked up about 12 dBi to the northwest. I usually now contact WD5ONS directly instead of having someone check me into ECN. The antenna is supported between two trees, with pully and weight for windy day allowance. The center is about 12 m above ground. The feedline comes to ground and then to a spark gap lightining arrestor mounted on an 8' ground rod. Then the feedline goes arond the cornor of the house to the ICE arrestor mountd on another ground rod, then into the outside junction box. Inside I have a knife switch that takes the feedline to the K1 or to ground. All ground rods have been connected together with nr 6 wire and also connected to the power company ground rod. The wife even let me put some holes in the wall for the feed lines. Junction box outside and another one inside so that future ideas of antennas can be implemented easily. With the new antenna I have worked W0CZ for ND and a random QSO with UT. AK and HI should not be to far away and I will make WAS, as soon as the QSL cards arrive. Getting on the air is so much more enjoyable with a good antenna. I even call CQ and get replies now (sometimes). Thanks Elecraft and the reflector for bringing me all the ideas that I could put together to make this work. 73, Ty, W1TF, GA K1 (4 band) - 1423 and BL2 __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] Open Wire Feed Line Arrestor
Morning Ralph, Thank you for sharing the information about these devices, very interesting! I must confess that I have for decades used NEW sparkplugs with their gaps suitably set for the maximum peak RF voltage on the line, assuming a high VSWR, plus some, and with separate static drains placed elsewhere. The devices that you have found probably provide better protection and are certainly neater. Knife switches and I have never got on very well!! I have always been wary of having to 'throw' a shack installed feeder switch in anger, probably because Murphy's Law states that this would be the moment when the antenna system gets zapped. But that's just one coward's opinion. Good luck with the double extended Zepp. 73, Geoff GM4ESD Ralph Tyrrell wrote on Friday, January 06, 2006 3:07 AM Still running my K1 (#1423) on inefficient low antennas. I have some trees that will give me good height 50-60' and orient the main lobe of a double extended zepp (14MHz) toward Oregon, take notice ECN. I have come across a device that will keep the antenna at near DC ground at all times. Just wondering if anyone else has used this or a similar item and what comments might be made. Just trying to be save from lightning. I would also put a DPDT knife switch between the feed line and the K1 with BL2 to ground the feed line when not in use. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] Open Wire Feed Line Arrestor
I used one for 5 or so years with a full wave 80m loop. It seemed to work well but I don't think I ever had a hit. I also had a knife switch, but in case I forgot to throw it or a storm snuck up on my, I had the ICE unit. On 1/5/06, Ralph Tyrrell <[EMAIL PROTECTED]> wrote: > > Still running my K1 (#1423) on inefficient low > antennas. > I have some trees that will give me good height 50-60' > and orient the main lobe of a double extended zepp > (14MHz) toward Oregon, take notice ECN. > > I have come across a device that will keep the antenna > at near DC ground at all times. > > http://www.arraysolutions.com/Products/ice/impulse1.html > > go down to "Open Wire Arrestor", Model 309 > > "All units use torroidal inductors and present near > dead DC short on antenna side of arrestor, constantly > draining feedline wires of static and any developed > voltage potential feedthrough breakdown voltage from > input ports to output ports 4,000 to 6,000 volts. > Arrestor units may be placed anywhere in the feedline > at ground level without serious change in tuning, but > small change may be detectable due "to small" increase > in total feedline length caused by size of arrestor > case & circuit." > > Just wondering if anyone else has used this or a > similar item and what comments might be made. Just > trying to be save from lightning. > I would also put a DPDT knife switch between the feed > line and the K1 with BL2 to ground the feed line when > not in use. > > Thanks all. > > 73, W1TF, Ty in GA > > > > __ > Yahoo! DSL – Something to write home about. > Just $16.99/mo. or less. > dsl.yahoo.com > > ___ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > -- - Jim ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] Open Wire Feed Line Arrestor
Thanks for the link. It's an interesting product. I had three reactions: 1) Note that the upper impedance specification is 600 ohms. Many (most) of our doublets produce impedances along the feed line much, much greater than that on some frequencies. That suggests the voltage ratings will be exceeded as well except at QRP or QRPp power levels. 2) I also noticed that they did not mention any loss figures. Anything tied between the feeder and ground will have some losses, so how much is of interest. 3) I would never use it expecting that it'd protect my rig from a close or direct strike. The surge from a "near miss" will be divided among the various paths. Even if the device handles hundreds of amps of surge, that may leave a very destructive current flowing through the rig in parallel. Ron AC7AC ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] Open Wire Feed Line Arrestor
I would take this quite a bit farther. I use open-wire feed for two major reasons. 1) It is super low loss no matter the SWR, without fear of high voltages burning up the feedline, and, 2) (directly related to #1) the antenna becomes inherently broadband with a suitable balanced tuner making it useful on 160-10 with just a retune. Adding anything (Ls or Cs) along the feedline could directly compromise #1 and affect the characteristics of the feedline. It would be very interesting to see the schematic of the device, but I am very skeptical as to it effects on the antenna system. It would probably have far less detrimental effects after that first close strike, however... I am very lucky to live in an area where thunderstorms are pretty much non-existent (maybe one a year), but when I was growing up in Miami I had to worry about this. Sparkplugs worked very well. I still worried though AND made sure the feedlines were thrown out the window any time there might be a storm. As for burying them underground, not MY open-wire line... ;-) On Jan 6, 2006, at 9:55 AM, Ron D'Eau Claire wrote: Thanks for the link. It's an interesting product. I had three reactions: 1) Note that the upper impedance specification is 600 ohms. Many (most) of our doublets produce impedances along the feed line much, much greater than that on some frequencies. That suggests the voltage ratings will be exceeded as well except at QRP or QRPp power levels. 2) I also noticed that they did not mention any loss figures. Anything tied between the feeder and ground will have some losses, so how much is of interest. 3) I would never use it expecting that it'd protect my rig from a close or direct strike. The surge from a "near miss" will be divided among the various paths. Even if the device handles hundreds of amps of surge, that may leave a very destructive current flowing through the rig in parallel. Ron AC7AC - Jack Brindle, W6FB, ex WA4FIB (Florida), ex WB5KQJ (Louisiana) - ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] Open Wire Feed Line Arrestor
The device is stated to have toroid cores on each side of the line conductor so as to provide a DC short to the antenna side of the box. On the transmit side, it may be AC coupled, which is fine when the right size cap is used for RF. The cores with their windings act as RF chokes while allowing a DC bleed off for any antenna charge. There was a similar device, (maybe the same reviewed in QST (?CQ) with a photo of the inside and it had pretty much the same circuit. Think that was last year or the year before. -Stuart K5KVH ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
