Best antenna for fringe channel 23?

[genx]

Hi, I am seeking your opinions on best GH model for this configuration.

Long range setup to obtain Watertown antenna from near ottawa, channel 18 (I think it is channel 23). Is there a model that has been optimized for this? I noticed GH 6 is optimized for higher channels so I dont think it would be for me.

I am thinking of building a DBGH10 rev2 but would this be best solution for my requirement? Having antenna with most gain for all channels is good so maybe this is option?

Thanks for your input, please note that I am looking for existing plans as I dont have modeling software. (not certain I want to try either )

[firimari]

The modelling software is free, and the established models are pretty much general purpose. If you want something tuned to a specific channel range, learning how to use the software is the best bet.

[mlord]

Originally Posted by genx

Long range setup to obtain Watertown antenna from near ottawa, channel 18 (I think it is channel 23). Is there a model that has been optimized for this?

The original SBGH10 design (not jedsoft's Rev.2) is very lopsided towards the lower UHF band (including 23), because that's what Autofils wanted to receive with it when he designed it.

That particular antenna is one of only two I have tried here that managed to receive WNPI-DT (UHF23), the other being our huge dual PR-8800 array.

If you like, I currently have a few loaner antennas for people like you, to try out and see what works (or doesn't). These include a UHF23-25 yagi, a PR-9032 corner-reflector yagi, a GH8 (jedsoft Rev.2), and other assorted devices.

email if interested: mlord at pobox daht com

Cheers

[genx]

mlord thank you very much for the feedback. I am just looking for a reason to build it I think it would be fun! I think OTA is great.

If the build does not work I will look at other avenues like modeling or trying other antennas. Cost or cosmetics is not primarily concern either right now, I just want the best antenna that I can build, preferably highest gain possible.

I have limits though, no more than 20' high and wide

[DdDave]

genx, are you looking for ONLY channel 23? Or go you want a full spectrum antenna with the best ch23 gain available?

[genx]

Originally Posted by DdDave

genx, are you looking for ONLY channel 23? Or go you want a full spectrum antenna with the best ch23 gain available?

Ideally a full uhf/vhf hi specturm antenna with highest possible gain curve at ch23. This way the anntenna can also be used for other channels. From what I am gathering from this site would not a GH10 DB version have more gain than any channel specific antenna?

[DdDave]

would not a GH10 DB version have more gain than any channel specific antenna?

If you build JED's GH10 version, the SBGH is listed to have net gain of about 14.8dBi. When you turn it into a DBGH, I believe the gain is about 2.5dB so you would end up with about 17.3dB. You would probably want to search around to see if anyone has modelled the DBGH version, because you may not get a full 2.5dB on ch 23. I know there was also some discussion about the optimum spacing between the 2 antennas, so you probably want to research that a bit also.

The other option you have is to redesign an XGH from JED for ch23. I don't recall seeing a ch23 XGH modelled yet, so you would have to learn the basics of one of the NEC programs to rescale it for your purposes. The XGH's get a liitle over 18dBi at the optimized frequency.

[mlord]

For a single channel, a custom yagi (or pair of yagis) is likely the highest gain solution. Easy to build too, but simulation/optimisation is needed to get the best impedance match.