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Re: [IRCA] DKAZ questions

I'm about 15 miles SSE of Boston. My situation with local stations, noise and interference is somewhat interesting. 

On MW I have WBZ and their 50kw blowtorch just to my NNE by about 4 miles but other than that I'm in good shape. I have very little noise (my noise floor on the ELAD at 500 khz is somewhere around -115). I have a switched termination superloop that is about 50x100 running SW/NE and a couple of Wellbrook ALA1530's (one is the S+ while the other is a borrowed older model). I have slightly more than 3/4 of acre so I can separate my antennas by about 90 to 100 ft. My problem is with phasing. No matter what configuration (altho I've yet to try the 2 Wellbrooks together) I find it hard not hear WBZ underneath the null (phase) on a number of frequencies. Even with a Chris Scott Associates AM tuneable notch I have phasing issues (the notch works perfectly on BZ without the Phaser however). In other cases if I don't hear BZ under the phase (null) I get a nasty hum. The one section of the AM band I do have some decent phasing luck is above 1200 khz but not always. 

On FM I have WGBH with 98kw about 7 miles west of me. No problems their except when pointing the FM antennas that way I have set the attenuation on the ELAD. 

Keith McGinnis 
Hingham MA 

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

From: "Mark Pettifor" <mark@xxxxxxxxxxxxxx> 
To: "Mailing list for the International Radio Club of America" <irca@xxxxxxxxxxxxxxxx> 
Sent: Friday, October 7, 2016 12:20:04 PM 
Subject: Re: [IRCA] DKAZ questions 

Lots of useful info - thanks to all! I think it would also be useful to 
tell you about my RF situation here in the Land of Goshen to get the 
best advice. 

1. I live less than two miles from 3 transmitters: 

-- WCMR 1270 AM. They are 5kW day, 1kW night. Bearing: NNW 
-- WFRN 104.7 FM. 50kW. Same site as WCMR. 
-- WSSM 97.7 FM. 6kW. Bearing: NNE 

I usually have to switch on attenuation for the ELAD via software (and 
for any other radio, really) when using my SE-NW longwire, which is 
about 150 feet long. The rest are OK without attenuation. That's a lot 
of RF flying about though. Growing up, we used to hear WCMR in all kinds 
of odd situations - sometimes just an improperly-grounded audio circuit 
would pick them up. I swear I heard their audio once coming from the 
heater vents from the furnace... 

2. There's a local RF noise source from somewhere - I think it's the 
neighbor across the road, using some kind of battery charger on the RV 
parked in their drive. We've talked briefly before, but I really need to 
take the time to get with him and identify the problem, and offer to 
help replace equipment or whatever it takes. It's pretty bad. Sometimes 
it even covers up the Detroit Tigers game on Kalamazoo's WKZO on 590, 
which upsets both myself and my brother, who lives next door. :^) 

Whatever the interference is, gets sent out the power lines from the 
neighbor's house, to the power pole. That section of power line is above 
ground, so it radiates the noise locally to whatever will receive it. 
What receives it best is MY power line coming to the house from the same 
pole, which is also above ground. So I've got "dirty" power coming into 
the house, as well as power lines transmitting it to the surrounding 
area. To get away from all that noise, I have to have the antenna about 
100 feet away from the house, on the opposite side from the road. 
Anything closer gets saturated with noise. 

Best solution is to identify the noise and eliminate it. The neighbors 
are nice people - I think I can get him to help narrow it down. Perhaps 
another solution would be to see if the power company will bury the 
power lines for both of us. It would involve going under the road though 
- the pole is on my side of the road. 

As I get older, I'm finding myself more willing to spend the money for 
"plug n play" solutions, but still, it's fun tinkering and rolling your 
own. Just a matter of time for me mostly right now - there are some 
other big time-consuming projects I need to address. 

Thanks for all the feedback! (If this were an audio forum, that would've 
been a pun...) 

Mark 

On 2016-10-07 11:25 am, Neil Kazaross wrote: 
> Unless one has some parts and wants to tinker, by far the easiest 
> solution 
> is go with a FLG100 from Wellbrook and a Vactrol from Colin. Both plug 
> and 
> play with cables and BNC connectors. 
> 
> 73 KAZ 
> 
> On Fri, Oct 7, 2016 at 9:52 AM, Nick Hall-Patch <nhp@xxxxxxxx> wrote: 
> 
>> Thanks Mark. I do think that your points about twisted pair are 
>> correct, 
>> and it would be intriguing to see if using twisted pair with the 
>> FLG100 
>> would make any further difference to the noise pickup. My suspicion 
>> is 
>> not, but it's only a suspicion. One of the things one seems to be 
>> paying 
>> for with the FLG100, as with the ALA100, is eliminating the concerns 
>> about 
>> noise being conveyed on the coax shield, which is what a balanced pair 
>> will 
>> do for you as well, at lower cost. 
>> 
>> The difference for me has been the "out of the box" nature of the 
>> FLG100 
>> solution. There are costs and costs, and time has been a big one of 
>> them 
>> in my years as a DXer. And once the FLG100 is up, there's been no 
>> tinkering with connections. 
>> 
>> One thing that has made twisted pair not "out of the box" for me has 
>> been 
>> the lack of remotely weatherproof connectors at a price that is not 
>> at 
>> least a down payment on a FLG100 (and yes, the BNC on the coax is not 
>> totally weatherproof, but a few inches of rubber tape is pretty 
>> close). 
>> If you have something that works well with CAT5 (banana plugs don't 
>> count; 
>> I've been troubleshooting with you, remember), then I am all ears. 
>> I 
>> think we discussed feed-through glands at one time. Is that what you 
>> have 
>> in mind? 
>> 
>> best wishes, 
>> 
>> Nick 
>> 
>> 
>> 
>> 
>> At 11:58 07-10-16, you wrote: 
>> 
>>> I do love the way the varied interests in this hobby are propagated 
>>> through this club from member to member and I'm grateful for the 
>>> knowledge 
>>> and experience that's so freely shared. 
>>> 
>>> One baby elephant in the room is Mark's antenna "ambience." If his 
>>> QTH 
>>> there in the Land O' Goshen is in a field of electrical interference 
>>> (and 
>>> perhaps significant local RF?), the noise gathered by the lead-in may 
>>> be an 
>>> issue best resolved not by common-mode choking but by "balancing" the 
>>> feed-lines. 
>>> 
>>> I've bored folks to death by espousing the balanced twisted-pair 
>>> approach, in the form of Category cable (Cat 5, Cat5e etc) with an 
>>> impedance around 110 ohms. IMHO such a BALANCED transmission line 
>>> pretty 
>>> much eliminates stray pickup without the need for common-mode 
>>> choking. 
>>> Cat-5 sells for around $45/1000 feet...although if the budget allows, 
>>> I'd 
>>> go for STRANDED Cat-5. 
>>> 
>>> As I type this I'm watching the Perseus on a D-Kaz facing mostly west 
>>> and 
>>> watching Seattle rolling in, here in North-Central Minnesota. Using 
>>> a 9:1 
>>> transformer and Cat-5 with a DXE RPA-1 in the shack and watching a 
>>> noise 
>>> floor of -111 dbm in 5 kHz, after the amplifier's 15 db gain. 
>>> 
>>> An absolute YES to the Vactrol approach for the null component. The 
>>> design for that circuit somewhat obviates the potential for stray 
>>> common-mode pickup, so coax may work FB, but again...twisted-pair is 
>>> so 
>>> easy to implement. 
>>> 
>>> As to mounting the RF amplifier at the antenna: I've tried the FLG 
>>> and 
>>> the DXE, planting them both at the antenna and in the shack. Like 
>>> Don 
>>> Moman, I can't really find any significant improvement...though in 
>>> theory 
>>> antenna-mounting of the amplifier is the better approach; weathering 
>>> issues 
>>> notwithstanding. (You would however, need a balancing transformer 
>>> after 
>>> the amplifier if you fed twisted-pair.) 
>>> 
>>> A winterized installation at my site would include twisted-pair 
>>> lead-ins, 
>>> a 9:1 transformer and a Vactrol control, mounted in weatherproof 
>>> boxes and 
>>> the amplifier in the nice warm shack. Amazon fans have found all 
>>> sizes of 
>>> weatherproof boxes and wire feed-throughs: 
>>> 
>>> At Amazon's greedy query, type in: "Cable Connect Waterproof Plastic 
>>> Case 
>>> Junction Box" and "Plastic Waterproof Cable Connectors" 
>>> 
>>> Decent transformers (if you don't have strong RF nearby) 
>>> http://www.minicircuits.com/pdfs/T9-1.pdf 
>>> 
>>> 
>>> Now for the famous YMMV <g> Have fun Mark; continue to share your 
>>> experiences! 
>>> 
>>> 
>>> Mark Durenberger, CPBE 
>>> 
>>> 
>>> -----Original Message----- From: Mark Pettifor 
>>> 
>>> Thanks for the advice guys - much appreciated! 
>>> 
>>> I should also publicly thank Tim Tromp for getting me interested in 
>>> the 
>>> DKAZ to begin with. 
>>> Mark 
>>> 
>>> On 2016-10-06 10:02 pm, Nick Hall-Patch wrote: 
>>> 
>>>> Agreed. They do cost a fair amount (mind you the exchange rate 
>>>> with 
>>>> the pound isn't bad right now), but are solidly built and work very 
>>>> well. 
>>>> Money well spent. 
>>>> 
>>> 
>>> Nick 
>>>> 
>>>> At 22:17 06-10-16, you wrote: 
>>>> 
>>>>> I very strongly recommend the Wellbrook FLG100LN, They go right at 
>>>>> the 
>>>>> antenna and replace your xfmr. Now what is picked up by the antenna 
>>>>> is 
>>>>> amped 22 dB whereas what is picked up by the coax is not amped at 
>>>>> all. 
>>>>> 
>>>>> I have two of these and they've survived IL weather for over 3 
>>>>> years. 
>>>>> 73 
>>>>> KAZ Barrington IL 
>>>>> 
>>>>> On Thu, Oct 6, 2016 at 4:29 PM, Mark Pettifor <mark@xxxxxxxxxxxxxx> 
>>>>> wrote: 
>>>>> 
>>>>> > For those of you who have DKAZ antennas, which preamp do you use? Do 
>>>>> > you 
>>>>> > find it makes much difference whether you put it at the antenna or in 
>>>>> > the 
>>>>> > shack? 
>>>>> > 
>>>>> > I need to "finish" construction on mine. Right now, I have two 470-ohm 
>>>>> > resistors alligator-clipped together for the null end, and a 
>>>>> hand-wound 
>>>>> > transformer (my first ever) on a core made of unknown material, to go 
>>>>> > from 
>>>>> > 940 to 50 into a 50-ohm feedline.... RG-8X, 150 feet. That is also 
>>>>> > alligator-clipped together. It was for testing, ya know? :^) 
>>>>> > 
>>>>> > It's been pretty good as is, but I want to get it ready to survive the 
>>>>> > winter. 
>>>>> > 
>>>>> > BTW, it's amazing the amount of noise just a short length of RG-8X 
>>>>> 100% 
>>>>> > shielded coax will pick up. I have it mostly on the ground, but have a 
>>>>> > small part of the run overhead for now (30 feet?) so I don't mow over 
>>>>> > it. 
>>>>> 
>>>> 
>>> > Thanks! 
>>>>> > 
>>>>> > Mark Pettifor 
>>>>> 
>>>> 
>>> > Near Goshen, INdx.com 
>>>>> 
>>>> 
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>> 
>> Nick Hall-Patch 
>> Victoria, BC 
>> Canada 
>> _______________________________________________ 
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>> IRCA, its editors, publishing staff, or officers 
>> 
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>> 
>> To Post a message: irca@xxxxxxxxxxxxxxxx 
>> 
>> 
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