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JVL DXer
06-05-2016, 10:20 AM
I think I'm really going to need a Yagi soon, I've gotten 250 logs (https://docs.google.com/spreadsheets/d/1Hj_qIvAZBQx-MTGqRs-Nko2tQzS-9o3_pEoTULyuudY) without one but, there's going to be a new translator on my 92.7 (250W at 250ft AGL) fcc shows it on top of WCLO tower and I know that WJVL has a 2 bay back-up up there. Anyway, I really wanted to get an FM-6 but I just cannot find any for sale online.

I did find this (http://www.mcmelectronics.com/product/30-2460?scode=GS401&utm_medium=cse&utm_source=google&utm_campaign=google&catargetid=530004080000291203&cadevice=t&gclid=CPy9iLf5kM0CFQmSaQodFJ8OsA) , it's also on Sears website. Does anyone know how this thing performs? Or is there another Yagi that I Should get?

H Hayes PA
06-05-2016, 11:58 AM
I have no direct experience with this antenna but if it were me I'd give it a shot at that price. It's small and could work indoors too, if need be. FM-6's are very hard to find nowadays, unfortunately. You can always upgrade if you find something larger.

JVL DXer
06-05-2016, 01:17 PM
I'm probably going to buy it but, I've have no idea what else I'll need with it.

egrabow
06-05-2016, 02:54 PM
It's certainly affordable. Please let us know if it's any good. I think RadioShack still sells masts and whatever other hardware you need.

Gary Hickerson
06-05-2016, 03:01 PM
JVL
You might want to get a "small" preamp, about 10 db. Just enough to give it a boost but keep down overload !

Gary H.

John Wilke K9RZZ
06-05-2016, 07:07 PM
I've been running the Stellar Labs 4 element yagi and their omni directional loop for several weeks, INDOORS on the second floor, and both work well in my opinion. I have a short 3 ft tripod with a 5 ft mast that both are mounted on. It sits on the floor in a spare room and is quite stable. Initially, I had lousy directivity from the yagi, but I was getting signal pick up from the 25 ft of RG-6 feedline. So I put a coax connector on the back of my receiver and use that instead of a balun and the stock wire connectors - problem solved. I consistently listen to Chicago stations 75 miles away and best DX has been Florida via E skip at 1,200 miles. For general monitoring, the loop hears very well. It is slightly directional like a dipole, but I've heard plenty of 100 to 200 mile tropo off the sides as well. For the size and price, I'd say you can't go wrong with either. :)

I'll try to get a snap shot of my antenna set up.

JVL DXer
06-05-2016, 07:14 PM
I'm confused, What did you do to help the directivity? Having a balun hurts?

John Wilke K9RZZ
06-05-2016, 07:24 PM
When I ran the RG-6 to a balun, then into the stock wire connectors on the tuner, I was getting signal pick up off the RG-6, messing up the directivity of the beam. So I drilled a hole in the back of the tuner, mounted a barrel F connector, ran a wire from that to the circuit board inside the tuner, and now the coax goes directly to the barrel connector - no more balun, no more feed line pick up, better directivity.

Very similar to what I did in my video 9:50 (https://youtu.be/YOTvlrtFNVI?t=9m50s) except on this current tuner, I don't have an attenuator switch.

JVL DXer
06-05-2016, 08:35 PM
Thanks for explaining, I get it now.

I just ordered it, hopefully it's good, I currently use just the bent but good antenna on my KA1103, headphones, or my homemade speaker wire zip tied to a broomstick that's ziptied to a pool pole that I have to hold up.

I'm curious what kind of difference a Yagi makes to just a pull out telescopic antenna, obviously it's better but, I've never used a Yagi or anything directional, for example can you get both the Rockford 103.1 and the spanish Chicago 103.1?

K4LY
06-05-2016, 08:55 PM
Does anyone know how this thing performs? Or is there another Yagi that I Should get?

I've used the Stellar Labs 4 el for over 8 months. It's a very good value and works well enough- like a 4 el FM antenna on a short boom should. K6STI modeled it. From recall, it's not as good as the FM-6, but close. Construction is only fair, but you can modify it so that it might hold up under icing. You might be able to add elements, too, for more gain. It's certainly worth the cost. I receive over 100 miles 24/7 with it on the few fairly open frequencies I have from the hilltop here in Inman, SC.

Mike-CT
06-06-2016, 12:00 AM
What makes this antenna a broadband antenna? All I see is one reflector, one dipole and two directors. Gain can't be much on this thing and with just two directors it can't be very directional. To me it almost has to be cut for one particular frequency, so if it's cut for 100mhz gain will drop as you go up or down in frequency from that point. Somebody correct me if I'm wrong on this.

John Wilke K9RZZ
06-06-2016, 01:50 AM
You are correct. It's as broadband as a folded dipole can be. Directional as a 4 element is. It's also just 66 inches long. It is what it is. If you need bigger, then you buy bigger. :)

I used to have a stacked pair of Winegard 6065p's up 45 feet. KILLER! I can't do that anymore, so for me, this fits the bill perfectly and I've logged 126 stations in the past month (new QTH).

(actually, those antennas are still up at the old house. Soooo tempted to hook up into 'em for one more spin of the dial. :cool: )

K4LY
06-06-2016, 08:54 PM
What makes this antenna a broadband antenna? All I see is one reflector, one dipole and two directors. Gain can't be much on this thing and with just two directors it can't be very directional. To me it almost has to be cut for one particular frequency, so if it's cut for 100mhz gain will drop as you go up or down in frequency from that point. Somebody correct me if I'm wrong on this.

Mike, I thought the same, but K6STI's modeling shows it covers 88-108 mHz pretty well with F/R being its weakness. The antenna is within a dB good as an unmodified FM-6-
http://ham-radio.com/k6sti/fm6.htm

For comparison, here is the stellar Labs-
http://ham-radio.com/k6sti/stellar.htm

Doug K4LY

JVL DXer
06-06-2016, 11:40 PM
Ugh, I had high hopes for this antenna, I hope it's much better than my current situation, a home made 300ohm wire folded dipole that sat outside most of the winter. But if there is any somewhat easy and inexpensive way to improve it I'd certainly like to hear about it!

I might not even have a way to mount the antenna, what I currently use is either the stock antenna on my KA1103 or headphones with the insignia, but getting to the point, I'm not sure I'll be able to mount it to the expandable pool pole(it's about 15ft fully extended) I currently have my folded dipole on. The site says it comes with mounting hardware, though I'm not sure the pole I currently have the folded dipole on is going to work, just to clarify I have nothing like the situation most of you have, I'm only 15 and my parents won't let me put anything permanent up, and if I want to use the folded dipole on the pool pole I have to constantly hold it upright in one hand and do everything else with the other. The Yagi will most likely be away most of the time as well, I used to put it in the patio table and that worked good until I had some friends over and they asked what it was for and I forgot to tighten the upper part and it collapsed and shattered the table. Anyways do you think that I can mount the Yagi to the pole? Currently it has about 15ft of extra co-ax on it and that probably affects performance. 187881878918790

John Wilke K9RZZ
06-07-2016, 01:57 AM
I think the yagi will clamp onto the pole okay. I'd probably tie your pole to a railing or something to hold it up while you're listening, otherwise you're gonna have your hands full trying to balance this thing one handed (and you don't want to knock it over and bend one of the elements! :) ).

egrabow
06-07-2016, 04:44 PM
I assume it came with a U-Bolt. That's your "mounting hardware".

If you have any floor-standing fans around the house you can borrow its stand and try what I do with my FM6. Mount the antenna to 6-feet of PVC pipe and insert it into the stand. It's not very high but it frees up your hands and can be easily rotated.

JVL DXer
06-11-2016, 02:02 PM
I've gotten the antenna now. I need a way to safely put the antenna away, but If I were to mount it to my,pole I'd have no way to store it without damaging the Yagi, right?

Also is there anyway to increase directivity? I can now hear 92.9 KATF (100kW at 83mi) clearly but no matter where I point the antenna I can't null it.

JVL DXer
06-11-2016, 04:00 PM
I feel like this is a really good antenna but maybe it's my radio that has some adjacent channel interference problems. Is there anything else that I could mount this to and not damage the antenna while storing it? 1880418805

JVL DXer
06-11-2016, 10:12 PM
Where would be the best point to mount to the boom? As in should I mount it to just behind the dipole or directly in the middle? I know that this can affect performance?

John Wilke K9RZZ
06-12-2016, 01:02 AM
Awesome, you've got it!

It's 4 elements, if you want more directivity, then you'll need a LONGER antenna with more elements. (or if you want to get crazy, then start antenna stacking and phasing. :) )

Even if you had 10, 12, 14 elements, there will be stations that you cannot null. The rule of thumb I keep telling myself is that no matter how big of an antenna you put up, you
can't force the band to open. You've still got to be patient and wait for the conditions you want.

The boom should be pre-drilled for the U-bolts for mounting to your mast. (mine was anyway, bolts included). All I had to do was bolt in on the mast, attach the coax, and go.

I'm having a blast with mine. :cool:

John Wilke K9RZZ
06-12-2016, 02:07 AM
I stand corrected, the boom is not drilled. It's a square boom and the mounting clamp goes around it. Just put it at the balance point. It can go anywhere, really, but why struggle. LOL

JVL DXer
06-13-2016, 09:34 PM
Don't know I should make a new thread for this but I've noticed that the directions stations are strongest is off quite a bit of where they actually are. It seems that WPWX is always strongest when I'm pointing directly east or just ENE even though Chicago is SE of me, And this is true for many stations! Also it seems like even my semi locals never come in perfect, there is always a faint fluttering sound, I have a good example in this (https://soundcloud.com/dx-from-wi/interference-while-using-yagi) clip, it starts with WPWX then I turn south and get WZPW then go back to WPWX and hear their TOH ID then i turn back to WZPW, you can hear the sound in the background.18812

John Wilke K9RZZ
06-14-2016, 12:45 AM
That's a good copy for 100 miles. This ain't no internet feed! :rolleyes: You might be getting some pick up off your feed line skewing the pattern. How to fix that? Hooked up to that little micro receiver ... I have no idea.

Stereotaco
07-06-2016, 04:58 PM
I just ordered a Stellar Labs 4 element yagi, I want to use my Marrantz 2200B that accepts a 300 ohm and 75 ohm antenna input. My question is do I need to use a balun transformer if I plan to use a coax feed line ?

Gary Hickerson
07-06-2016, 05:57 PM
If your receiver has a 75 ohm connector on the back, you don't need a balum. Its built into the receiver. If it just has screw terminals, only, then you do.

Gary H.

Mike-CT
07-06-2016, 11:47 PM
But you do need a balun when connecting the RG6 to the dipole on the antenna.

Stereotaco
07-07-2016, 03:31 PM
[QUOTE=John Wilke K9RZZ;39938]When I ran the RG-6 to a balun, then into the stock wire connectors on the tuner, I was getting signal pick up off the RG-6, messing up the directivity of the beam. So I drilled a hole in the back of the tuner, mounted a barrel F connector, ran a wire from that to the circuit board inside the tuner, and now the coax goes directly to the barrel connector - no more balun, no more feed line pick up, better directivity.

Very similar to what I did in my video 9:50 (https://youtu.be/YOTvlrtFNVI?t=9m50s) except on this current tuner, I don't have an attenuator switch.[/QUOT

I have a couple questions about this....
Would this conversion be worth doing on a Marrantz 2200b Receiver
What parts would I need besides some wire and a panel mount F connector ?

Stereotaco
07-07-2016, 03:37 PM
I have a 300ohm folded dipole that is connected to a 4 position barrier terminal block on one side and the RG6 center pin and shield connected to the other, on the other end of the coax I have a 300ohm to 75ohm balun connected to the antenna input of my marrantz 2200b receiver, is this the correct way to connect a dipole antenna ?

Mike-CT
07-07-2016, 04:41 PM
I found the back of a Marantz 2275 from eBay and scribbled down how the antennas are connected.
You can run RG6 straight into the tuner. Shield goes to ground and the center conductor goes to the 75ohm block.
Perhaps your tuner is similar.

If you don't strip the RG6 and you connect it to a balun on the receiver end instead, you connect the balun leads to ground and the 300 ohm block on the right end.

Stereotaco
07-07-2016, 04:55 PM
Does it matter what end the balun is connected at ? at the receiver or at the antenna feed point ?

Mike-CT
07-07-2016, 05:50 PM
A dipole and that 4 element yagi are 300 ohm devices. The coax is 75 ohms. So you need a balun at the antenna itself. Now if you look at the diagram on my other post you will see that you can connect the coax to the receiver two different ways. If the tuner has just 300 ohm screw terminals then you need a balun there on that end also. If it has a 75ohm connection point then you connect the coax the way I showed you without any balun.

Stereotaco
07-08-2016, 01:50 PM
Should I add a RF choke and if so what do you recommend ?

JVL DXer
07-10-2016, 07:09 PM
I didn't and I have about 20ft of extra co-ax on mine, works good though.