Sweet Antennas Direct DB8 and AntennaCraft Y10-7-13 Mods!

EscapeVelocity

Moderator, , Webmaster of EV's Antenna Blog
#1
Remember that fellow that did the Spectrum Analyzer A/B testing of 8 bays and the xg91....well he has some great mods he developed as well. The DB8 was just posted today!

A Modifed Antenna Craft Y10-7-13

A Modifed AntennasDirect DB8

I really like the corner reflector extentions on the DB8 and the closed end bowties are nice too.

The Plane Reflector is sweet on the AntennaCraft 10 Element VHF High Band.


Those things are HUGE!
 

EscapeVelocity

Moderator, , Webmaster of EV's Antenna Blog
#2
I love the pic of the snow and ice capped xg91 and modded Y10-7-13!


I am in touch with the fellow, and will be sending out a Kosmic SuperQuad for him to test with the rest of his collection. He will probably have an old discontinued American made CM 4228A as well.

Best

EV
 
Last edited:

EscapeVelocity

Moderator, , Webmaster of EV's Antenna Blog
#4
Sometimes easy is good! I think the modder above as much as admitted that ganging 2 DB8s would probably yeild good results and be a whole heck of a lot less work.

 

Piggie

Super Moderator
#5
Were I really into this again, rather than going with a long-boom, a pair of stacked unmodified antennas might be just as easy. I may yet try this with a second Antennacraft FM6, as I once did with my Finco FM-4Gs.
Damon, I too took the stacked route if you have read other threads here or AVS on YA-1713's stacked vertically. However not to slight the antenna but they still don't give me enough Front to Back to reject Tampa (and I am asking for a LOT of F/B). I am not sure I could get enough front to back to reject tropo from Tampa short of a metal wall or tall fence behind the antenna.

What I find interesting about his Y10-7-13 reflector mod was I thought about the same thing for a YA-1713, but lacking good aluminum tools and motivation, I never even went past a though of that would be good. CushCraft came out with a 2 meter long boom yagi (144-148 MHz and tunable to be useful over about 2 MHz), that had a similar reflector stock. Besides a single dipole element normally used as a yagi reflector they also mounted one above and one below the plane of the yagi and about half the distance behind the "regular" reflector compared to the distance from the driven element to that "regular" reflector. I don't remember the name of that antenna except "Boomer" but they built a lot of antennas by that name. Anyway it had an exceptional null off the rear, with just 2 additional elements similar to the modified Y10-7-13.

Then one to stacking FM antennas. I have never personally tried stacking the FM6, but I knew of a guy that did back in the 1980s (then sold under the Radio Shack name). He ended up stacking 4 of them, since he didn't get what he wanted from 2 of them. The band was less crowded then and he wanted to be able to hear everything from Jacksonville, Tallahassee, Tampa and Orlando from his house in Gainesville FL, all in the 70 to 130 mile range. I can say sitting in his living room it worked on at least the strong stations. He combined them with simple splitters to cover the whole band.

Not sure what I would do now for FM. But I think just on paper I would choose to buy a longer boom yagi for FM instead of stacking 2 FM6 antennas. As you probably know doubling the boom length is very close to the same thing as doubling the number of stacked antennas or in the 3 db range.

Though I believe there are still advantages to stacking. Horizontally yagi's give you a very tight beamwidth and often excellent F/B. Stacked vertically, they are easy to mount and give a tighter beam width at a lower angle of radiation (speaking in transmitter terms).

I feel I proved out to some degree the benefits by stacking my YA-1713's vertically. When I point at WNBW that is 470 watts ERP at 37 miles, yet LOS, I can't see a lot of difference between my 3 element beam, a single YA-1713 or my stack of two of the latter. But and a huge but, when I point at Jacksonville at 61 miles and 2-Edge the stacked pair really shines (kicks the llama's behind). The 3 element at Jax (short for Jacksonville FL) doesn't stand a chance, far from a lock. A single YA-1713 lets you know they are there but not usable. When I added the second one at 40 inches (for channel 13) things came alive! My quality meter jumped over 10 points, which is huge on it from my experience (Toshiba 26 inch tube 480i widescreen). I attribute this to lowering my angle of reception to a tighter lobe pointed at the horizon where edge signals are strongest normally. Now if I just could kill Tampa from the rear but when tropo rolls here in the Gulf states it's strong, very strong, often stronger than the desired "local" station's signal. I learned this decades ago on 2 meters where mobile in my car in town, running 10 watts ERP from the roof of my car, I could talk to the Orlando 146.22/82 repeater 80 miles away, only up a couple hundred feet. It would only work if the local repeater here in Gainesville were not triggered on. If they both came on at once and even though I was less than 10 miles from the Gainesville repeater running twice the ERP at 600 ft, the result was nearly equal signal with neither repeater capturing my receiver. So tropo on a regular basis is very strong around here when it happens.

Back in the day of using OTA antennas for cable head ends, a few early (mom and pop size in those days, circa 1970's) used very low antennas for 50 to 100 mile paths. One in particular was the old Alachua/High Springs FL cable head end. It was chain link fence in an arc from the ground to about 12 to 18 feet high. Then antennas were mounted on short poles about 6 to 8 feet off the ground pointed at that huge reflector, each in it's own focal point for the station it was receiving. This was the only way they could get rid of most of the tropo trying to serve their customers back then. Back then they were pulling in WFTV and WDBO (now WKMG) from Orlando on 9 and 6 respectively at about 90 to 100 miles.
 

Piggie

Super Moderator
#7
Sometimes easy is good! I think the modder above as much as admitted that ganging 2 DB8s would probably yeild good results and be a whole heck of a lot less work.
But just aesthetically, his mods made some very beautiful antennas, in all seriousness. Then again I like that sort of thing!
 

Piggie

Super Moderator
#8
I love the pic of the snow and ice capped xg91 and modded Y10-7-13!


I am in touch with the fellow, and will be sending out a Kosmic SuperQuad for him to test with the rest of his collection. He will probably have an old discontinued American made CM 4228A as well.

Best

EV
I hope Winegard sends him some samples. That would be interesting.
 
Top