Wouldn't you need to compensate for the velocity factor of the coax when making it 1/4 wavelength longer though? I guess that is what they mean by electrical quarter wavelength.Yes, that's exactly what he did (http://www.digitalhome.ca/forum/showpost.php?p=1411982&postcount=27), using the velocity factor of 0.85 that was specified by the manufacturer of his coax.

The wavefront of the incoming signal arrives at the upper antenna sooner than the lower antenna, so you need the extra coax to act as a delay line so that the signals from the two antennas arrive in phase at the combiner.

^^^Sorry, I didn't see any mention of velocity factor in his original (or suubsiquent) posts.

No problem; it took me a long time to go through his posts because I was very interested in high F to B ratios after trying to help Balm with VHF-hi WVNY reception at his summer cottage in Saint Anicet.

How's the DB4e for FM reception. Seems to work but I'm noticeably missing 2 strong local stations from Toronto (about 40 miles away). From those nearby, the 2 stations are CHUM(104.5) and the Q107.

^^^The DB4e will be about as good for FM as it is for VHF-LO and that is very poor. Strong broadcasts will be receivable by anything, but you will be better off with a simple FM folded dipole.

Roger is quite correct. UHF antennas will work for FM about as well as the power cord on your bedside clock radio. Short-range reception is usually okay, but beyond that, a real FM antenna should be used.

I apologize if this is in the wrong thread

(US) Walmart is now selling 2 Antennas Direct HDTV antennas , ClearStream Micron and ClearStream1

Walmart Embraces Cord-Cutting Movement
(http://www.prweb.com/releases/2012/5/prweb9530506.htm)

Please note they're being positioned in the aisle with the Roku-type products instead of with the other antennas and accessories.

Individual store setups may vary.

ADTech, any idea if it will come to Walmart Canada? It would also be nice if they sold the indoor C2 (and C2V) as well.

Need some advice for the DB2e and the DB4e

I've used a DB8 in the past. But since I've moved recently, I have a DB4 temporally placed at a window picking up all the Montreal stations (except for CFJP-DT 35.1) and also WCAX, WPTZ and WCFE from the US. Not bad really for a indoor window placement.

Summer time is here and it'll be time to do a proper roof top install. I'm in a Condo building that allows Dishes and such on the roof. So no problem.
But, at the same time, I would like to use a small footprint antenna on the roof.

The question is which one. Would a DB2e be good enough to replace a DB4, or would I require a DB4e instead. I won't use the DB4 I have as I have promised it to somebody else.

The set up would be on a six storey building. No obstructions, can see Mount Royal, and have a clear path towards the US. The only thing that concerns me is the airplane path as they prepare to land at the local airport. But that would be on the back end of the antenna. The RG6 run would be 6 floors down, and then another 30 to 40 feet back up.

Comments, Suggestions appreciated.

Roger is quite correct. UHF antennas will work for FM about as well as the power cord on your bedside clock radio. Short-range reception is usually okay, but beyond that, a real FM antenna should be used.
FWIW, my experience was quite different. I bought a proper FM antenna but it overwhelmed my tuners ( 2 or 3 stations could be found on about half a dozen frequencies as I scanned through the frequencies). So I took it down (still for sale BTW :-) ) and put up a UHF antenna to see what would happen - it worked great!

In the Radio forum on this site, the experts advised my that the tuners in your average stereo receiver are likely poor and work better with low gain antennas (like that little white wire that came with mine). True, I only get local stations but it was still MUCH better than what a proper FM antenna yielded. My location probably isn't the best either.

^^^I am assuring when you say a proper FM antenna, you mean a high gain Yagi. Given your location, a high gain antenna of any type will likely cause problems and you are better off with something that has a little less gain. That doesn't necessarily mean you are better off with a UHF antenna that has negative gain on FM (though maybe in extreme cases you are if you need the attenuation). A low gain FM antenna might be a better option in most cases.

Roger,

I don't know. WMT Canada is a completely separate company as far as purchasing goes. We just started shipping to WMT USA last month so it would be hard to imagine the Canadian side doing anything in the near term. Yes, it would be nice to have an expanded selection, but there are tow major obstacles: 1) Shelf/floor space commitment and 2) the buyer from WMT only wanted the least expensive antennas in the ClearStream line to put on their shelves. I'd really like to see the C2v on retail store shelves because it's needed so often, but, corporate buyers being what they are, don't see it from the same perspective as a technical person does.


Blackburst,

The DB2e is pretty darned close to the original DB4 in peak gain across most of the band, but the 4-bay bowtie will have a narrower vertical beamwidth which can help reduce aircraft-induced multi-path. I prefer to recommend the DB4e over the DB2e around airports because it does give a little bit of an advantage in fighting this particular issue.


El gran Chico,

See Roger's reply. You may have been overloading your FM tuners or the high-gain FM antenna was mis-aimed. For close-in work with no multi-path, a simple automobile antenna, new or recycled, oriented vertically, is usually sufficient.

Cheaper radios dont usually have tuners with high enough selectivity to tune in many stations with high gain antennas and/or amplification.

I just wonder if a DB4e can receive VHF (namely, CTV channel 9 in Toronto)?

thanks

Elty,

I strongly get channels 10 and 12 at a nine mile distance with any 4 bay antenna that I make.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d267eee22a6d100

Any UHF antenna will receive VHF, it will be at a significantly lower level though (if your close and/or its analog - it may suffice sometimes).

Yes, it may work with strong VHF signals, but it won't be a good VHF antenna.

RE: photo in Post #310 (http://www.digitalhome.ca/forum/showpost.php?p=1347103&postcount=310):

I'm thinking of doing one of these myself, but I would want to use aluminium cross-braces like you did in in the photo. I have everything I need for cabling and combining, but can you guys sell me a couple of braces and clamps like those shown here?

Those are just re-used from a scrapped DB8.

You'll need to improvise or scrounge something up locally. We tend to haul off scrap aluminum and steel for recycling.