NMO34 with the W640 (64" whip) vs NMO-27 vs CWB-27

[RFI-EMI-GUY]

The only thing I don't like about this one is it brings us right back to a short whip. But I am starting to like it just because of what it can do.

Apparently Laird has a 10/11m antenna that is wide band:

C27S: CB Radio & 10M Whip Antenna for 27-31 MHz with Spring Base. Equivalent to 102 Inch Whip Antenna.

The Laird - Antenex C27S is a 1/4 wave, unity gain CB radio antenna that is tunable for CB frequency range (26.965 - 27.406 MHz) and 10 Meter range ( 28 MHz - 29.7 MHz). This antenna comes with spring base which provides increased flexibility, better shape retention, and eliminates electronic...

www.arcantenna.com

The C27 Laird is tunable, not wideband like CW27. Much confusion as Google fu substitutes the C27 for CW27.

 

[KX4KDH]

The C27 Laird is tunable, not wideband like CW27. Much confusion as Google fu substitutes the C27 for CW27.

Crap. They got me again. They should have said "antenna that is tunable for CB frequency range (26.965 - 27.406 MHz) OR 10 Meter range ( 28 MHz - 29.7 MHz)".

 

[mrweather]

“Reduces” (freq spec), or, one needs to reduce height (length) to maintain original tune?

Well, to maintain the same resonant frequency you'd have to shorten the whip to account for the spring.

But I don't see why you couldn't maintain the whip length, insert the spring and benefit from an electrically longer antenna and resulting reduced resonant frequency?

 

[slowmover]

Well, to maintain the same resonant frequency you'd have to shorten the whip to account for the spring.

But I don't see why you couldn't maintain the whip length, insert the spring and benefit from an electrically longer antenna and resulting reduced resonant frequency?

My interest is almost strictly 11M. Best possible equates with longest/tallest antenna re details of such.

If it can play that Skynyrd song, FreeBand, then it’s gold.

NMO27 (“standard”) ain’t got what it takes. Leaves too much on the table with what latest radios can do (even older ones).

As part of what to recommend to most men this thread we’re in is great. This link to another thread is the “why”:

Post in thread 'Anytone AT-6666'
Anytone AT-6666
(The one previous is intro)

Leveraging todays NRC radios, but with a low-key “best built” antenna system.

 

[KX4KDH]

My interest is almost strictly 11M. Best possible equates with longest/tallest antenna re details of such.

If it can play that Skynyrd song, FreeBand, then it’s gold.

NMO27 (“standard”) ain’t got what it takes. Leaves too much on the table with what latest radios can do (even older ones).

As part of what to recommend to most men this thread we’re in is great. This link to another thread is the “why”:

Post in thread 'Anytone AT-6666'
Anytone AT-6666
(The one previous is intro)

Leveraging todays NRC radios, but with a low-key “best built” antenna system.View attachment 173054

Yes. This is what I have, except it’s the updated Quad 6 Pro model. So far, a stellar radio for what it is. And also why I wish I could find one antenna that can cover both 10, and 11m.

 

[RFI-EMI-GUY]

I drilled out the whip holder on one of my CW27s and put on a whip about .124" dia at the base. Not for more BW but to make it stiffer. I don't think you'll get any more BW out of an NMO34, that's why Laird and Panorama made WB versions with a fancy coil.

PRCGUY;
What is your opinion of the CW42 bandwidth? If you look at all the bands :
CW27= 2.9 MHz
CW30= 4 MHz
CW34= 6 MHz
CW42= 6 MHz
It seems they may be understating the BW of CW42. Has anyone trimmed the whip to center this antenna a bit higher and encompassed the range 43.04 to 52.525 or higher MHz?

 

[prcguy]

View attachment 173505
PRCGUY;
What is your opinion of the CW42 bandwidth? If you look at all the bands :
CW27= 2.9 MHz
CW30= 4 MHz
CW34= 6 MHz
CW42= 6 MHz
It seems they may be understating the BW of CW42. Has anyone trimmed the whip to center this antenna a bit higher and encompassed the range 43.04 to 52.525 or higher MHz?

I’m away from home at the moment but I can test a CW27 next week. I may have a spare CW37 to test at home and I have one on the roof of the place I’m at right now but don’t have any whips here to swap out.

 

[prcguy]

Looking at the innards of a CW27 and CW37 there might be resonant LC components for the intended frequency range that may not play nice if you change whip length for a different frequency range. We can try another whip length and measure VSWR but I think a field strength measurement is also needed to make sure the antenna efficiency is not affected.

 

[RFI-EMI-GUY]

Looking at the innards of a CW27 and CW37 there might be resonant LC components for the intended frequency range that may not play nice if you change whip length for a different frequency range. We can try another whip length and measure VSWR but I think a field strength measurement is also needed to make sure the antenna efficiency is not affected.

Edit I neglected to include CW37 in the listing which really makes the point that CW42 should/could be much wider:
PRCGUY;
What is your opinion of the CW42 bandwidth? If you look at all the bands :
CW27= 2.9 MHz
CW30= 4 MHz
CW34= 6 MHz
CW37=9 MHz
CW42= 6 MHz
It seems they may be understating the BW of CW42. Has anyone trimmed the whip to center this antenna a bit higher and encompassed the range 43.04 to 52.525 or higher MHz?

 

[prcguy]

Edit I neglected to include CW37 in the listing which really makes the point that CW42 should/could be much wider:
PRCGUY;
What is your opinion of the CW42 bandwidth? If you look at all the bands :
CW27= 2.9 MHz
CW30= 4 MHz
CW34= 6 MHz
CW37=9 MHz
CW42= 6 MHz
It seems they may be understating the BW of CW42. Has anyone trimmed the whip to center this antenna a bit higher and encompassed the range 43.04 to 52.525 or higher MHz?

The CHP had a contract for the CW37 antenna to cover their complete VHF lo frequency range and was probably the biggest customer for these. I wonder if the CW37 was custom designed for CHP? Otherwise every antenna type has a certain % of BW and the higher you go in frequency the more MHz it will cover and it’s usually very predictable if the antenna type is mechanically proportional at different frequencies.

But the Laird CW series doesn’t fit the mold with the CW27 having 10.74% BW, CW30 with 13.33% BW, CW34 with 17.64% BW and the CW37 with 24.32% BW, but the CW42 is down to 14.28% BW. There could be design constraints with the matching circuit or Antenex/Laird is targeting specific radio services for each model or something else is going on here that I don’t understand.

 

[RFI-EMI-GUY]

The CHP had a contract for the CW37 antenna to cover their complete VHF lo frequency range and was probably the biggest customer for these. I wonder if the CW37 was custom designed for CHP? Otherwise every antenna type has a certain % of BW and the higher you go in frequency the more MHz it will cover and it’s usually very predictable if the antenna type is mechanically proportional at different frequencies.

But the Laird CW series doesn’t fit the mold with the CW27 having 10.74% BW, CW30 with 13.33% BW, CW34 with 17.64% BW and the CW37 with 24.32% BW, but the CW42 is down to 14.28% BW. There could be design constraints with the matching circuit or Antenex/Laird is targeting specific radio services for each model or something else is going on here that I don’t understand.

I am wondering if it is simply a marketing limitation. The Part 90 Public safety pool ends at 47.66 MHz. The IB pool extends much higher to 49.58 but is interspersed with cordless phones. Maybe a decision was made to move the sweet spot / longer whip, into the public safety pool for efficiency reasons.

 

[KX4KDH]

If only they still made the CW27.

 

[slowmover]

If only they still made the CW27.

Agreed. NOW is that time it comes into its own.

 

[RFI-EMI-GUY]

I am attempting to find if Laird will process a bulk order of CW-27 or CWB-27. I was pursuing a source of NOS in Hong Kong but that turned out to be a likely scam outfit. If anyone is interested, give me a shout on direct conversation.

 

[mmckenna]

I am attempting to find if Laird will process a bulk order of CW-27 or CWB-27. I was pursuing a source of NOS in Hong Kong but that turned out to be a likely scam outfit. If anyone is interested, give me a shout on direct conversation.

After all the singing of praises, I might be tempted to purchase one if you get them to do a batch. Hell, put me down for two. Seems like if you could get them to do this, and find a way to let them let you resell them, you could make some pretty good coin.

 

[slowmover]

Second.

I’d really like to compare one to the expensive antennas I have (when mount included) as I want to see a great NMO we can use as persuasion that a high-performance CB isn’t difficult. Or “goofy”.

I’m happy with my choices . . . but I also have experience most others won’t ever acquire.

— More than half of Americans live in a major metro region where the “big” 7’ roof-center antenna benefits aren’t obvious such that a low key 6’ would be great!



So there’s zero reason to fall beneath a certain threshold to accommodate “the look” if the right NMO can be sourced. (And I can then send it along to my son for one of his vehicles).

If times got tough? Then from preserving fuel range, etc, to being in contact with a family/friends set of base stations just became priority for vehicle use. (Justification).

I’ve posted a number of times how my $1,300 big truck radio rig repays itself 3-4X annually.

But it’s not strictly about ROI. It’s about leveraging the value of one’s vehicle. Lowered operating costs on a CPM basis usually correlates with lowered driver stress.

I stayed longer in the city on errands this evening. An easy choice despite a long day and being tired. As a major accident closed the Interstate just before my usual exit heard from 14-miles out. Re-routes and delays of over an hour past dark. On a holiday night.

By the time I rolled past in my 9,000-lb pickup it was as if it hadn’t happened. My Average MPG stays at 22 for all miles thereby as my Average MPH remains high (engine time versus miles).

— I’m not in traffic where the benighted are doing STOOPID things to try to go around. A major wreck tends to spawn subsidiary wrecks.

And so forth.

.

 

[KX4KDH]

After all the singing of praises, I might be tempted to purchase one if you get them to do a batch. Hell, put me down for two. Seems like if you could get them to do this, and find a way to let them let you resell them, you could make some pretty good coin.

These folks claim to have 1,280 of the CW-27. Not shocking that they are in HK. Maybe one of us can do an RFQ for a bunch of them?

https://www.infinite-electronics.net/product/Laird-Technologies-Antennas_CW27.aspx

 

[mmckenna]

These folks claim to have 1,280 of the CW-27. Not shocking that they are in HK. Maybe one of us can do an RFQ for a bunch of them?

https://www.infinite-electronics.net/product/Laird-Technologies-Antennas_CW27.aspx

Not sure if it's the same guys that was mentioned below:

I was pursuing a source of NOS in Hong Kong but that turned out to be a likely scam outfit.

I don't want Cheap Chinese Antennas. $27 sounds fishy.

 

[KX4KDH]

Not sure if it's the same guys that was mentioned below:


I don't want Cheap Chinese Antennas. $27 sounds fishy.

It may be the place RF-EMI-GUY mentioned, and somehow I missed that post.

You say you don’t want cheap Chinese antennas. Are we sure this isn’t where they were made to begin with? I do tend to agree with you, I’m just not sure where Laird products are made.

I did put in an RFQ for a quantity of 1, and haven’t heard back (as expected). Nobody wants to sell just one.

 

[mmckenna]

It may be the place RF-EMI-GUY mentioned, and somehow I missed that post.

You say you don’t want cheap Chinese antennas. Are we sure this isn’t where they were made to begin with? I do tend to agree with you, I’m just not sure where Laird products are made.

I did put in an RFQ for a quantity of 1, and haven’t heard back (as expected). Nobody wants to sell just one.

I have some Laird antennas purchased from reputable sources, and they are pretty good antennas. Some report issues with base coil cracks, but I've never experienced it myself, even on UTV installs.

It's entirely possible that they are made in China.

But what I've found is that Tram/Browning seems to have a LOT of knock off looking antennas that look extremely similar to known name brands. Like maybe Chinese factories that make the OEM antennas also producing for other manufacturers. Some may be 'just as good' and have a different brand name on them. Some may be factory seconds that get resold under a different name. But we know that the Chinese have no issue at all selling forgeries whenever it suits them. What should be a $50 antenna being sold on line for $27 makes me skeptical.

I personally don't see value in buying a possible knock-off antenna to save a few bucks. I'd rather have known good name brand products and pay for them. Hasn't backfired on me yet.

The fact that Laird is not selling these themselves makes me suspicious. Dealers like Tessco, The Antenna Farm or others aren't showing them as available raises my suspicion.