Metoer Detectors

Hi all

sorry to trouble you

I want to make a meteor detector using my Yupietru MVT7000 Scanner/detector
and a Di-Pole aerial.

I have seen it done before to good success but am unsure how to do it or
what to buy.

Can anyone point me to a web site that tell me what size di-pole to buy
(From Maplins) maybe? and the frequencies I need to set my Yupiteru too in
order to hear the meteor Pings along with how to construct one?. I also
understand that you have to be careful of overflying aircraft as they give a
ping too.

Thanks in advance

Andy

you can email me off group or in group

Hello
You may have a little look at my site (in french) there is a page
about my installation.

and some links
http://radio.meteor.free.fr/us/main.html
http://www.imo.net/radio/

good luck


On Sat, 19 Feb 2005 00:31:36 GMT, "Andy"
wrote:

Hi all

sorry to trouble you

I want to make a meteor detector using my Yupietru MVT7000 Scanner/detector
and a Di-Pole aerial.

I have seen it done before to good success but am unsure how to do it or
what to buy.

Can anyone point me to a web site that tell me what size di-pole to buy
(From Maplins) maybe? and the frequencies I need to set my Yupiteru too in
order to hear the meteor Pings along with how to construct one?. I also
understand that you have to be careful of overflying aircraft as they give a
ping too.

Thanks in advance

Andy

you can email me off group or in group



Best Greetings From SWITZERLAND
Philippe HAAKE
ICQ 3128404
http://astrosurf.com/skylover/
http://astrosurf.com/skylover/meteo
http://www.astro-ge.net/
http://community.webshots.com/user/beruberu1


beruberu@NOSBSPAMfreesurfDOTch
!!!!!!REMOVE NOSBSPAM FROM MY E-MAIL!!!!!!

Spammers, here are some email addresses for your spambots:


$LOGIN@localhost $LOGNAME@localhost $USER@localhost
$USER@$HOST -h1024@localhost admin@loopback

or one from Chris Heapy

http://easyweb.easynet.co.uk/~chrish/radio-met.htm

....but don't ask me!
"Philippe HAAKE" wrote in message
...
Hello
You may have a little look at my site (in french) there is a page
about my installation.

and some links
http://radio.meteor.free.fr/us/main.html
http://www.imo.net/radio/

good luck


On Sat, 19 Feb 2005 00:31:36 GMT, "Andy"
wrote:

Hi all

sorry to trouble you

I want to make a meteor detector using my Yupietru MVT7000
Scanner/detector
and a Di-Pole aerial.

I have seen it done before to good success but am unsure how to do it or
what to buy.

Can anyone point me to a web site that tell me what size di-pole to buy
(From Maplins) maybe? and the frequencies I need to set my Yupiteru too in
order to hear the meteor Pings along with how to construct one?. I also
understand that you have to be careful of overflying aircraft as they give
a
ping too.

Thanks in advance

Andy

you can email me off group or in group



Best Greetings From SWITZERLAND
Philippe HAAKE
ICQ 3128404
http://astrosurf.com/skylover/
http://astrosurf.com/skylover/meteo
http://www.astro-ge.net/
http://community.webshots.com/user/beruberu1


beruberu@NOSBSPAMfreesurfDOTch
!!!!!!REMOVE NOSBSPAM FROM MY E-MAIL!!!!!!

Spammers, here are some email addresses for your spambots:


$LOGIN@localhost $LOGNAME@localhost
$USER@localhost
$USER@$HOST -h1024@localhost admin@loopback

In article , Andy
writes

Can anyone point me to a web site that tell me what size di-pole to buy
(From Maplins) maybe? and the frequencies I need to set my Yupiteru too in
order to hear the meteor Pings along with how to construct one?. I also
understand that you have to be careful of overflying aircraft as they give a
ping too.


I'd second the advice from Philippe and Paul and add the following.

The most popular frequencies to try, for Western European observers, are
the vision carriers of distant European TV transmitters. The best bets
a

The West European E channel vision carrier -

48.25 MHz
49.75 MHz
55.25 MHz
62.25 MHz

France vision carriers

55.75 MHz
60.50 MHz
63.75 MHz

East European "R" channels

49.75 MHz
59.25 MHz
77.25 MHz
85.25 MHz
93.25 MHz

All frequencies from World Radio TV Handbook 2004.

The MVT7000 doesn't have USB or LSB modes, so you'll be best to use AM.

You'll need to offset your receiver frequency slightly (by about 1KHz)
from the frequencies given above, as you'll be attempting to listening
to the heterodyne beat generated between the TV transmitters vision
carrier and your receivers local oscillator. So for a transmitter on
48.25 MHz, you'll tune to either 48.249 MHz, or 48.251 MHz and you'll
hear pings at around 1KHz audio frequency . All the TV carriers transmit
with a slight frequency offset too, to reduce co-channel interference
between transmitters, so the tone generated will not be exact. I think
this will work in AM mode - it certainly would in single side band mode.

Initially, find a frequency that looks promising - generally quiet and
no constant tone - using any old antenna you can find, or make - just a
long wire will be fine initially. Then if you get serious, you'll need
to buy an aerial that covers the frequency you plan to operate at and
ideally should be directional and aimed towards the target transmitter.

Meteor activity is generally low at the moment and particularly low in
the early evening. Don't give up if you don't hear an obvious ping in
the first few minutes - things will pick up slightly in the early
morning and it is never long before the next shower comes along.

Good luck.
--
David Entwistle

David Entwistle wrote:
In article , Andy
writes

Can anyone point me to a web site that tell me what size di-pole to
buy (From Maplins) maybe? and the frequencies I need to set my
Yupiteru too in order to hear the meteor Pings along with how to
construct one?. I also understand that you have to be careful of
overflying aircraft as they give a ping too.


I'd second the advice from Philippe and Paul and add the following.

The most popular frequencies to try, for Western European observers,
are
the vision carriers of distant European TV transmitters. The best bets
a

The West European E channel vision carrier -

48.25 MHz
49.75 MHz
55.25 MHz
62.25 MHz

France vision carriers

55.75 MHz
60.50 MHz
63.75 MHz

East European "R" channels

49.75 MHz
59.25 MHz
77.25 MHz
85.25 MHz
93.25 MHz

All frequencies from World Radio TV Handbook 2004.

The MVT7000 doesn't have USB or LSB modes, so you'll be best to use
AM.

You'll need to offset your receiver frequency slightly (by about 1KHz)
from the frequencies given above, as you'll be attempting to listening
to the heterodyne beat generated between the TV transmitters vision
carrier and your receivers local oscillator.

No no no - you are explaining what to do if it did do USB/LSB/CW.
But AM isn't going to beat with anything that provides an audio beat
note as there's no BFO (CIO) to provide it.


--
Graham W http://www.gcw.org.uk/ PGM-FI page updated, Graphics Tutorial
WIMBORNE http://www.wessex-astro-society.freeserve.co.uk/ Wessex
Dorset UK Astro Society's Web pages, Info, Meeting Dates, Sites & Maps
Change 'news' to 'sewn' in my Reply address to avoid my spam filter.

In article ,
Graham W writes

No no no - you are explaining what to do if it did do USB/LSB/CW.
But AM isn't going to beat with anything that provides an audio beat
note as there's no BFO (CIO) to provide it.


Hi Graham,

Doesn't it depend on the AM detection system used? If the MVT7000 uses
none coherent envelope detection then, as you say there'll be no beat.
However, if the MVT7000 uses synchronous AM detection there will be.

Having said that, you're probably right. A receiver that isn't equipped
for single side band operation is unlikely to have synchronous AM
demodulation.

Any suggestion as to what Andy could try to increase his chances of
hearing meteors, with a AM/FM/WFM receiver?
--
David Entwistle

David Entwistle wrote:
In article ,
Graham W writes

No no no - you are explaining what to do if it did do USB/LSB/CW.
But AM isn't going to beat with anything that provides an audio beat
note as there's no BFO (CIO) to provide it.


Hi Graham,

Doesn't it depend on the AM detection system used? If the MVT7000 uses
none coherent envelope detection then, as you say there'll be no beat.
However, if the MVT7000 uses synchronous AM detection there will be.

Having said that, you're probably right. A receiver that isn't
equipped for single side band operation is unlikely to have
synchronous AM demodulation.

Any suggestion as to what Andy could try to increase his chances of
hearing meteors, with a AM/FM/WFM receiver?

He really does need to have a BFO but this could be just an external
coil/capacitor/transistor osc. which is tuned to the IF centre F and
placed
very close near to the receiver. Does it use 455kHz AM IF?


--
Graham W http://www.gcw.org.uk/ PGM-FI page updated, Graphics Tutorial
WIMBORNE http://www.wessex-astro-society.freeserve.co.uk/ Wessex
Dorset UK Astro Society's Web pages, Info, Meeting Dates, Sites & Maps
Change 'news' to 'sewn' in my Reply address to avoid my spam filter.

In article ,
Graham W writes

He really does need to have a BFO but this could be just an external
coil/capacitor/transistor osc. which is tuned to the IF centre F and
placed
very close near to the receiver. Does it use 455kHz AM IF?


Thanks Graham,

I'm not sure what the MVT7000 intermediate frequencies (IFs) are - I've
only managed to find a user manual, in Swedish, on the web and that
doesn't say. However, if we assumed that it does, I sense you have a
cunning plan...?

The alternatives, for Andy, appear to be to build the external beat
frequency oscillator (BFO) you're suggesting, or to upgrade to a
receiver that does offer at least one of the following modes - upper
side band (USB), lower side band (LSB) and continuous wave (CW) modes. A
model like, but not limited to, the Yupiteru MVT-7100.

General advice for any astronomer thinking of buying a scanner, and
considering meteor work, should be to make sure it offers all three of
the above modes (USB, LSB and CW) in addition to the standard AM, FM and
WFM. Should you plan to log meteor counts, it is also desirable that it
have a mains power supply option and an audio line output. Does that
seem fair?

--
David Entwistle

David Entwistle wrote:
In article ,
Graham W writes

He really does need to have a BFO but this could be just an external
coil/capacitor/transistor osc. which is tuned to the IF centre F and
placed
very close near to the receiver. Does it use 455kHz AM IF?


Thanks Graham,

I'm not sure what the MVT7000 intermediate frequencies (IFs) are -
I've only managed to find a user manual, in Swedish, on the web and
that doesn't say. However, if we assumed that it does, I sense you
have a cunning plan...?

The alternatives, for Andy, appear to be to build the external beat
frequency oscillator (BFO) you're suggesting, or to upgrade to a
receiver that does offer at least one of the following modes - upper
side band (USB), lower side band (LSB) and continuous wave (CW)
modes. A model like, but not limited to, the Yupiteru MVT-7100.

I found this which may do if the AM IF is in the ~455/470 kHz range:
URL:http://www.wsplc.com/acatalog/Kits_Ten_Tec.html
it is the third item down and is less than a tenner!



General advice for any astronomer thinking of buying a scanner, and
considering meteor work, should be to make sure it offers all three of
the above modes (USB, LSB and CW) in addition to the standard AM, FM
and WFM. Should you plan to log meteor counts, it is also desirable
that it have a mains power supply option and an audio line output.
Does that seem fair?

Agreed, it does.


--
Graham W http://www.gcw.org.uk/ PGM-FI page updated, Graphics Tutorial
WIMBORNE http://www.wessex-astro-society.freeserve.co.uk/ Wessex
Dorset UK Astro Society's Web pages, Info, Meeting Dates, Sites & Maps
Change 'news' to 'sewn' in my Reply address to avoid my spam filter.

i used to listen on 50mhz to the radio ham anglsey beacon on 50.15 (i
think) it was way down in the noise but if a meteor came the signal of
the beacon would rise up to "s9" sometimes

cheers, john