Comet Miracle-Baby mobile?

[nanZor]

Right - so part of the GRE/Whistler game has always been that 800/900 mhz has a hot front end. Heh, used to be a selling point when all people looked at was the sensitivity specs.

In an rf-dense area like mine, the dinky Comet CH-32 Miracle Baby makes a great fit for the HT, usually attenuator off, but sometimes on even then!

When I went mobile with the 1040, I STILL wanted to get that thing outside the cabin - and used a small bnc-magmount for the Miracle-Baby. Worked pretty well, but as always, YMMV. It was easy to just remove and stash in the pocket in high-theft areas.

I use it with the current '1040, and used it with the predecessors, even the mobile units (rooftop mag-mount with the Comet obviously) and it tamed the front end to a reasonable state.

At the end of the day, I do remind myself that these are inexpensive wideband scanners, and not like the dedicated radios we use at the company.

 

[rayvelcoro]

Glad you had good results with the Comet. Stubby wideband antennas have never agreed with my TRX-1's for some reason.

 

[eyes00only]

Glad you had good results with the Comet. Stubby wideband antennas have never agreed with my TRX-1's for some reason.

I'm glad you posted that because I was suspicious. That's a lot of money. I wish I could find the best antenna for 700 & 800 MHz
to use on my TRX1. Of course I still have VHF & UHF that I monitor too.

 

[nanZor]

Part of the expense is that unlike just a simple resistor inside, they can actually be transmitted into on amateur frequencies for the most part with low power.

But you gotta' watch out - there are Miracle-Baby "look alikes" that are cheap replicas, not resonant at all at 800/900 mhz. Some amateur bullet antennas are dual-band vhf/uhf - and resonant near 1200mhz. Even so, sure, they "can" receive other bands. Just not very well.

One has to watch out - PAPERCLIPS can be marketed as "wideband scanning antennas" - and they'll pass the legal test.

The idea here is that being resonant on/near the amateur bands, high-reactance out of band helps lower the noise floor on the front-ends.

That high reactance out of band is the reason I recommend for vhf air-banders the Icom FA-B02AR, rather than the canonical RH77 - which is good, but it's out of band reactance for airband is not as good (on purpose!) as the Icom. Same with the Miracle-Baby, provided you don't get a cheap counterfeit. Helps Whistler / GRE front-ends in both cases when heavy rf environments are encountered.

Where the high out-of-band reactance antennas really shine is with the older dual-conversion models, say the WS1010 and others that may not have the best dual-conversion image-rejection. Using a *real* Comet CH-32, or the Icom airband transceiver duck can really open them up. I've even used the Icom duck mobile too and it stays pretty stiff at freeway speeds.

But yeah, you're going to pay. Might be a small price to pay in the end after dropping a few bills on a TRX-1, and finding the front-end getting hammered.

 

[eyes00only]

nanZor,

If you could only have one antenna on a TRX1 for 50% P25 Simulcast & 25% UHF DMR & 25% VHF Conventional,
what would you buy?

 

[nanZor]

In my rf-dense area, if I had to choose only one for those purposes stated above, it would be the Maldol MH-209 (bnc or sma) version. There are other little small-bendy types that aren't full length out there - but aren't bullets either.

Being slightly larger than the Miracle Baby, yet not full-size, it is the most appropriate fit for my Whistlers front end. Being just slightly longer than the Miracle baby, not being truly resonant in the 800/900 mhz band is not a problem, whereas that is welcome with the Comet.

Although designed for amateur 2m/70cm resonance, the Maldol is just fine for nearby business bands. Low band - not serious, that needs something else, but the flamethrowers are easily heard.

For me, that's my best general-purpose antenna for the Whistler's front end. Some systems STILL need attenuation, but not many. When I go hard core specific, like airband, I specialize.

That's the thing with the Whistlers - it depends on the op's location and interests. Kind of part of the fun of finding out what works best for *you* as your duck-drawer collection expands.

 

[rayvelcoro]

nanZor,

If you could only have one antenna on a TRX1 for 50% P25 Simulcast & 25% UHF DMR & 25% VHF Conventional,
what would you buy?

The old Radio Shack 800 Mhz rubber duck antenna which is supposedly identical to the Remtronix 800 Mhz rubber duck, has been the superior all-around performer on my TRX-1's, hands down. Perhaps not for airband or low band though. Apparently, this is a popular opinion with which I agree.

 

[nanZor]

The RS800 / Remtronix as a good 800/900 mhz antenna. On a real transceiver that would be fine. But unfortunately, in my area, running with those is just total overload on the Whistler's at 800/900 mhz.

That's kind of always been the GRE/Whistler way - 800mhz was waaay hot in gain. Which is ok out in the boonies. But rf-dense areas usually always need the attenuator, or plenty of experimentation with things like the Comet Miracle-Babies or other small antennas tuned or specifically made for 800 mhz, where the normally excellent RS800 is just too much.

I'm kind of strange though - I actually enjoy experimenting with different antennas on my scanners depending on the service they are doing at the time.

You know - after all these years we still don't know if the attenuator is pre-or-post of the first rf-amplifier. That can make a difference.

That means sometimes a small tuned antenna with no attenuator provides better results than say an RS800 with attenuator on. The key is to find what works for you the best...

 

[rayvelcoro]

The RS800 / Remtronix as a good 800/900 mhz antenna. On a real transceiver that would be fine. But unfortunately, in my area, running with those is just total overload on the Whistler's at 800/900 mhz.

That's kind of always been the GRE/Whistler way - 800mhz was waaay hot in gain. Which is ok out in the boonies. But rf-dense areas usually always need the attenuator, or plenty of experimentation with things like the Comet Miracle-Babies or other small antennas tuned or specifically made for 800 mhz, where the normally excellent RS800 is just too much.

I'm kind of strange though - I actually enjoy experimenting with different antennas on my scanners depending on the service they are doing at the time.

You know - after all these years we still don't know if the attenuator is pre-or-post of the first rf-amplifier. That can make a difference.

That means sometimes a small tuned antenna with no attenuator provides better results than say an RS800 with attenuator on. The key is to find what works for you the best...

As far as the TRX-1 goes, I read somewhere that monitoring P25 simulcast with the attenuator on even in a dense RF area doesn't really help much. What do you think about this?

 

[eyes00only]

The old Radio Shack 800 Mhz rubber duck antenna which is supposedly identical to the Remtronix 800 Mhz rubber duck, has been the superior all-around performer on my TRX-1's, hands down. Perhaps not for airband or low band though. Apparently, this is a popular opinion with which I agree.

That's the one I'm using now that I had on my GRE PSR500 and it works okay. There is a lot of 700 MHz in my area and that's my main
problem. I do have about 7 antennas but none improve on the above one. I may give the Maldol a try depending on the cost. The only
store in my area is Ham Radio Outlet and they're really expensive.
Thanks for the replies.

 

[rayvelcoro]

That's the one I'm using now that I had on my GRE PSR500 and it works okay. There is a lot of 700 MHz in my area and that's my main
problem. I do have about 7 antennas but none improve on the above one. I may give the Maldol a try depending on the cost. The only
store in my area is Ham Radio Outlet and they're really expensive.
Thanks for the replies.

I usually search online but look for an actual antenna business to help avoid counterfeits.