Antenna testing terrible srh77ca

[nanZor]

In this thread, I think only myself and the OP actually own this antenna; everyone else is just reading the specs and drawing assumptions.

I will admit that I'm testing the bnc-version of the RH77 and not the sma-type, although I wouldn't think that would make a difference.

Out of curiosity I put all the antennas I buy on an MFJ-269B, going from N-sma or N-bnc adapter. I only use the MFJ analyzer body as the case to emulate a typical handheld - no ground plane attached and running from batteries. (I don't want the wall-wart cord to provide it's own groundplane so to speak.)

The RH77CA is very wideband at VHF HI / Low. Interestingly, the least amount of reactance with about 47 ohms resistance reads about 158 mhz. At UHF, I can only measure SWR without the reactance and it is under 3:1 across 430-450.

But SWR doesn't tell the whole story for efficiency, as the super-stubby Diamond SRH805S also has low swr across the bands for TX.

Our testing methodology is different. Instead of using s-meter bars, I listen for signals just above the noise and compare the quieting. In some cases I'll just throw in the attenuator to get the signals low, and then swap antennas and listen for quieting. (Not on AM of course, but you can tell the difference.

My RH77 is relatively new - maybe your 6-year old version has an 800mhz spike inside? Just conjecture unless we open them up.

 

[darticus]

Really feel bad that the DIAMOND COMPANY advertises this for a scanner which its really no good for in wide band range. I also wonder why the Diamond company has not gotten back to me it a response to its antenna not being able to do the advertised job and maybe give me a trade up or something. I emailed Diamond about a week ago. Hope it doesn't take them 2 months before they get back like some companies do. I also hope some have opened their eyes to the fact that maybe your Diamond is not doing what you expect but are taking Diamonds word for it. Ron

 

[W4KRR]

It's very difficult to have one single antenna that performs equally well on more than one or two bands. The Diamond is going to work best on 2 meter and 440 MHz ham, but that is what it was designed for. Yes, it will receive on 800MHz too, but so will a paper clip, to some extent. I find that the RH77CA does well for me, but if I want better reception on the 800MHz band, then I switch to a dedicated 800MHz antenna, such as the Radio Shack branded one, or ones from GRE or Antenex.

You might want to try the Austin Condor. It was designed to be a tri-band receive antenna for VHF high, UHF, and 800MHz. It too works well, but many people don't like it because it's long, fat, and more expensive than many other antennas. In the scanning world, low profile and best performance usually don't go together, you must choose one or the other.

 

[QwKiE]

I know what you bought

But you bought the wrong antenna. Should have told you to buy a Diamond SRH789 sma antenna I use one on my home patrol 1 and it works fine for everything including up to 1100 only 29.95. I don't know anything about the rh77ca but I looked it up and they all say for the lower frequiencies not the 800 band. I did see the package you showed. Thats whats wrong. But most advertising says only good for 2 meters and 440 MHz.

 

[WA1ATA]

Yes, it will receive on 800MHz too, but so will a paper clip, to some extent.

In my actual tests, a paper clip does BETTER than the standard rubber ducky antenna.

A standard paper clip is just under 4" long, and a bit skinnier than the center pin of a BNC male or SMA male connector. So outside of being a tiny bit too small to make good contact, a paper clip stuck directly into the antenna connector of a scanner is actually a pretty good 800MHz antenna.

Don't knock it until you've tried it. :lol:

Obviously, a 3.5" antenna is much shorter than a 1/4 wavelength on VHF airband and vhf, but it still does a reasonable job, and is actually pretty good at 460MHz.

 

[QwKiE]

We understand

But everyone don't want a paper clip hanging out there $600.00 radio where you can see its a paper clip.
LOL

 

[skidplate]

I see the problem

darticus,
Diamond states the antenna in question is for use in receiving those other bands on an "HANDHELD TRANSCEIVER". You appear to be using it on a scanner. I have 2 RH77CA's, one is on a kenwood th-f6a. As soon as I started using it on the kenwood I noticed big improvements in signals as well as my fuel mileage went up, I cut my electric bills in half, my hair regrew, and I no longer have spots on my dishes.
In all seriousness though, most people that use that antenna are satisfied with what they have exchanged money for. You are not. It is not Diamond's fault that you choose to live in a location where one of the products they sell does not work exactly as you would want. If the stock antenna that was designed and included with your scanner was already working why not get a refund on the Diamond and use the stocker or invest in an antenna designed for the frequency band that you actually are targeting. Like so many have pointed out, there is no perfect , do all antenna or radio.

 

[SCPD]

I think the difference maybe that those of us that had good experience with the RH77 have the BNC version and the OP has the SMA version mine (the BNC) works great as a rx antenna anywhere I've tried and on tx in the ham bands people sometimes won't believe that I'm on an HT with a rubber duck. Or possibly their quality control has suffered as most people praising the antenna have older ones(mine's probably more than 10 years old).

 

[eorange]

I've had the BNC version for 13 years, and again the SMA version for 6+ years. Interchanged them on many radios (scanners, HTs, wideband receivers), and they both work exactly the same.

To the OP: nothing we say can make it work better for you on 800 MHz, but if you ever get into civil or military airband monitoring - keep it. It's a real winner there.

 

[DPD1]

I got curious and put one on the network analyzer. Yes, it's not exactly awesome in the RX bands. But it's not hideous either. I wouldn't hold your breath on Diamond doing anything. They don't give any gain claims for those bands... just the TX bands. They just say it can receive in the other bands. Which it does do. Just not with any gain. Which is the same any antenna is going to do. There really isn't any such thing for a handheld that's going to do everything well. It's just not possible to make something like that. You can get stuff that will do one or two bands well. Not everything. And same goes for most simple antennas advertised as "25-1300". A ground plane, or even something with multiple elements, is really still just focusing on a couple bands. You get the other stuff by default. Manufacturers say stuff like that, because if you just said 440 and 2M or something, then people would assume it wouldn't get anything at all in other bands. Which is usually not the case. Most antennas will be passable in other bands they weren't specifically designed for.

 

[KI4VBR]

One More Comment On This....

I was mobile the other day, listening on my 396XT with the SRH 77 and getting fair 800 mhz. signals at best. I decided to take the 77 off and switch out to the stock antenna that came with the XT. Well, when I unscrewed the antenna off of my radio, there was NO CHANGE in signal quality or strength! None....I still picked up the county Type II system with nothing screwed into the SMA.

My point is that the SRH 77 performed exactly as good as having nothing for an 800 mhz. antenna....go figure. Of course I put the stock antenna on to compare and it took the marginal signal up to Q5, full quiteing. I was surprised to see this happen, so I did it with another radio and got similar results. I dont know how far I was from the tower, but I know it was not within 1/4 mile. If anyone is familiar with Pinellas county in FL, I was on Bayshore (Alt. 19) & Curlew roads, trunking the RIdgecrest tower.....maybe someone knows how far this was.

So I thought I would shake up the thread and share my little report with anyone interested. I am curious if others can dupe the same results. Also, when I am out on the beach with lots of open area, it performs very well listening to the VHF marine band, Aviation as well as a number of UHF repeaters I use.

Vince

 

[PHOENIX_SCANNER]

Ah yes, the magical antenna....

Kind of like the 800mhz antenna that is supposed to do miracles according to so many, when it fact it is scarcely better than the stock antenna at 800mhz, and worse on VHF Hi. Generally on 800mhz you are dealing with digital these days around here, and either the signal is good and you can listen, or it is weak and you are going to have problems, and no antenna is going to do any magic. To me it is of no value, and I've tested it plenty. Might as well use the stock duck. But so many will tell you how it makes this HUGE difference....not in my testing....

Now on to the subject at hand, the Diamond RH77. I've used it for a few years for every type of reception on multiple radios, and feel I can give a fair assessment for my individual situation.

VHF high: Superior to stock duck, absolutely no question, especially for civilian air band listening.
450/460 mhz UHF: Similar to stock duck performance, with a bit of an edge.
Milair: FAR better than a stock duck, no contest.
700/800 mhz: similar to stock duck.

Now since I like to catch the local F16 squadrons, sometimes on the go, I keep one on my 106, despite it being huge and silly looking. It also helps with the ancient VHF High system that Phoenix FD still clings onto (years after PD went to 700/800 P25). Does it offer an advantage for some? Yes, it does. Is it the best choice for someone mostly listening to 700/800 mhz stuff? No. In my view just use the stock duck and call it a day, no need for silly "800mhz antennas" either, the stock duck does that fine.

 

[Fidgety9996]

Thanks, Maybe you have corrected me and I am wrong. I just know its terrible for a hand held scanner and it was recommended very highly for its use. The packaging for it has me confused as it does say it will do the job for 800 band. If I wrong again sorry if I'm right this has a false advertisement but its good for something else. Ron

this looks like counterfeit