49Mhz anyone?...

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radiosification
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Re: 49Mhz anyone?...

Post by radiosification »

bigbloke wrote:I'll wire the 6m dipole and preamp onto the spec analyser later and show you a plot of 49.6 to 50MHz
I'd be interested in seeing that too :)
If you're interested in digital voice, check out my YouTube channel:
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wind in the antenna
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Re: 49Mhz anyone?...

Post by wind in the antenna »

Here's what the Band II broadcast band looks like around here

Image

and the 49MHz SRD band (centred on 50MHz)

Image

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Re: 49Mhz anyone?...

Post by bigbloke »

Yep, some big local49 sigs there Tony! -40 to 50 dBm UGGH!

BTW ive heard italian cordless phones on 49FM tonight down
around 49.500-600 some seriously good E-s here intermittently.
I have the DTMF decoder board in the AOR5000+3 and the area codes
dialled suggest northern end of central italy

Worked italy and Portugal on the FT817 on a 1.5m telescopic whip
around 8-9pm on its internal battery too. the Portuguese guy was 60 over 9

Annoying hearing the italians going back to north america about 2 hours ago -
nothing heard from stateside here this cycle ...yet!

I remember back in the late 70s early 80s with my SX200-A listening to new york cabbies on low-band , and at least one "call girl" dispatch. wonder if gypsy cabs are still down there.

Regards

BB
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Re: 49Mhz anyone?...

Post by bigbloke »

Heres a plot from 49 to 50 Mhz using just a dipole and "good" masthead preamp this evening.
49-to-50.JPG
Admittedly, this was in the middle of a significant "E" opening

As the path was north south here there was no video Buzz from R1 at the time

its centred on 49.5 and roughly 60 KHz / div on the vertical graticule
bottom of scale was set to -60dBm but the preamp was in line. horizontal scale is roughly
10dBm per graticule

the local baby monitors can clearly be seen around 49.880 - BIG signals :(

The "flat top" spike just below 49.5 is an italian cordless phone via E's
The big spike around 49.330 is an italian voice enabled on site pager TX
you'll notice the pager tx from italy is as strong as the one from one of the local
hospitals (49.635 ish)

the little peaks in the low 49-49.3 were mainly data signals , probably via E's

absolutely mad on there tonight !!

regards

BB
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Re: 49Mhz anyone?...

Post by Powermax »

brianford5mhz wrote:
wind in the antenna wrote:In any case, xtals aren't that expensive if you're buying them in quantities of thousands rather than having them individually cut to resonance.quote]

They may be cheaper in bulk, but even then they form a huge amount
of the cost compared to the other components and it's market value.

And what is the market value of a pair of Spaceman toy handhelds ? Not a lot ;-)

Changing the subject slightly, I have fond memories as a kid being given
a pair of these 49Mhz AM walkie talkies.

One transistor regeneratove receivers and a few milliwatts of tx.

I remember having the bright idea at 10 years old of attaching a wire to the
aerial to see if I could improve the range. Something amazing happened !

Because 405 line telly from Crystal Palace was on the air on Band 1, my
crappy receiver brought it in, and Top of the Pops came through on it.

Thrilling for a kid then and I soon learnt the art of DX'ing for life :-)

I had a similar experience. Once night time fell, I started picking up TV sound!
Of course that will no longer be an issue.

As someone else has rightly said, the receivers in these units are poor. My scanner can hear the signal a good way after the other receiver has given up.

They also benefit from a proper aerial. Back in my kiddie days I didn't know that aerials had to be the right wavelength, I just connected a long wire to my set and incoming reception improved markedly. Never did any proper Tx tests but I'm sure it was the same for them.

I'm not sure what the output power of the chinese sets from the 70's were but I doubt it was even 10mW
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Re: 49Mhz anyone?...

Post by handyguy2002 »

hi guys

I have 4 headsets that my kids used to play with,, and they are on 49.405 on AM, Im not sure weather to keep them as my kids dont use them now as the radios dont go far,,
Binatone 950
QuanSheng TG-UV2
TYT 380 + TYT 9600
Kirisun S780
Uniden +BCT15x + BCD396t +BCD536 hp
HYTERA PD505
WHISTLER TRX2
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Dagnabbit
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Re: 49Mhz anyone?...

Post by Dagnabbit »

Never heard any down there amongst the paging, are you sure it's not higher up 49Megs at around 49.8-50?
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Re: 49Mhz anyone?...

Post by radiosification »

Dagnabbit wrote:Never heard any down there amongst the paging, are you sure it's not higher up 49Megs at around 49.8-50?
That's because the range is so awful :lol:
If you're interested in digital voice, check out my YouTube channel:
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Re: 49Mhz anyone?...

Post by Dagnabbit »

Ha :D

Yes, Google is full of 49.405, somehow that had passed me by, never seen any reference to it before.
i.e. Channel X according to http://www.geocities.ws/gccengineering/49mhz.html
handyguy2002
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Re: 49Mhz anyone?...

Post by handyguy2002 »

hi guys


my scanner picks them up at 49.405 on AM,,, I dont have a freqancy counter so cant check them carrectly,,
Binatone 950
QuanSheng TG-UV2
TYT 380 + TYT 9600
Kirisun S780
Uniden +BCT15x + BCD396t +BCD536 hp
HYTERA PD505
WHISTLER TRX2
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Re: 49Mhz anyone?...

Post by pmr446man »

49.860mhz
pmr446 king.
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Dagnabbit
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Re: 49Mhz anyone?...

Post by Dagnabbit »

Surprised to find the band totally clear at home last night. For years I'd had several strong baby monitor signals on several channels, but now nothing. All the kids around here have obviously grown up!
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Re: 49Mhz anyone?...

Post by GlasgowSnapper »

Cedwards wrote:
wind in the antenna wrote:Well I guess whatever the reason for the distribution of practically all SRD49 in the UK being confined to the bottom 5 channels, we have the 5 top ones to play around with knowing that we won't be causing anyone any bother. I like the idea of 459.950 being a calling channel as it's reachable on a radio with 25 kHz steps

:twisted: :twisted: :twisted: :twisted: :twisted: :twisted: :twisted: :twisted:

Image
:twisted: :twisted: :twisted: :twisted: :twisted: :twisted: :twisted: :twisted:
What radio is that
That's a PRC352 - basically a PRC351 plus a 20 watt amp.

The boxes are, from top to bottom;

*SURF (Selective Unit RF) - allows radios to be used in close proximity to each other without causing interference.

*PRC 351 radio - the base 4W radio.

*20W amp - used with ground spike antenna.

*24V battery pack.
2M0FRA
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kr0ne
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Re: 49Mhz anyone?...

Post by kr0ne »

Is it just me or is this thread a little late this year? :lol:
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Re: 49Mhz anyone?...

Post by MrWeetabix »

well if anyone in the North East wants to play, I can do 49mHz, as well as 50mHz, so let me know :ugeek:
26TM175. OP: Craig. QTH: Gateshead IO94EW. Also 163TM175 when mobile in Wales 8)

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