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micro UHF transmitter
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mildex
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Post micro UHF transmitter Reply with quote
I am looking for schematic diagram of micro UHF transmitter(bug), frequency band near 400MHz (quarz controlled) ,range near 500m or more, professional SMD design, small size, battery life 10-20 days. Could someone advice good solution?

mildex
Tue Oct 21, 2003 5:58 pm View user's profile Send private message
pcs
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http://www.pcs-electronics.com/en/products.php?sub=fm_bugs



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Marko - PCS Electronics
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Tue Oct 21, 2003 10:00 pm View user's profile Send private message Visit poster's website
mildex
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I need more professional and more quality bug then listed here, I need Schematic diagram.

mildex
Wed Oct 22, 2003 10:37 am View user's profile Send private message
pcs
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Post Reply with quote
You must be kidding. The PRO version is exactly what you're
looking for, gives up to 2km of range with 20 days of battery
life. Its crystal - PLL controlled. And it is UHF.

You are right about one thing, though. Schematic is not available
for this unit.

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Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Wed Oct 22, 2003 11:45 am View user's profile Send private message Visit poster's website
mildex
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I'd always prefer build unit independently, this allows choose/customize some options, case size, power etc. Why do not make the schematic diagram AVAILABLE for community? This topic calls "User share experience..." Community could discuss its, maybe, even to improve some parameters. There many good specialists among a community.

mildex


pcs wrote:
You must be kidding. The PRO version is exactly what you're
looking for, gives up to 2km of range with 20 days of battery
life. Its crystal - PLL controlled. And it is UHF.

You are right about one thing, though. Schematic is not available
for this unit.

Wed Oct 22, 2003 3:55 pm View user's profile Send private message
pcs
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Post Reply with quote
Did you make your TV set yourself also?

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Wed Oct 22, 2003 6:56 pm View user's profile Send private message Visit poster's website
mildex
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Post Reply with quote
No, I do not make my TVset myself. This is other thing, its outside of my interests.

pcs wrote:
Did you make your TV set yourself also?

Thu Oct 23, 2003 10:59 am View user's profile Send private message
pcs
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Post Reply with quote
The BUG PRO I is a product of another company of my very close
friend. He does not want to publish a schematic.

BUG PRO I is a pretty unique piece of transmitter and I don't see
a reason why he should give away the schematic. He would be crazy
to do so. Also, it is entirely SMD with some really hard to get parts,
custom ordered Xtals etc. So it is not suitable for a homebuilder as
such. Just making the PCB is very complex at this frequency.

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Thu Oct 23, 2003 11:06 am View user's profile Send private message Visit poster's website
mildex
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Post Reply with quote
Here is description and schematic of good VHF bug
http://hem.passagen.se/communication/buggtx.html
You can use it for free.

pcs wrote:
The BUG PRO I is a product of another company of my very close
friend. He does not want to publish a schematic.

BUG PRO I is a pretty unique piece of transmitter and I don't see
a reason why he should give away the schematic. He would be crazy
to do so. Also, it is entirely SMD with some really hard to get parts,
custom ordered Xtals etc. So it is not suitable for a homebuilder as
such. Just making the PCB is very complex at this frequency.

Thu Oct 23, 2003 3:19 pm View user's profile Send private message
pcs
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Post Reply with quote
Hi!

Thanks for the schematic, I'll add it to our schematic section.

I have a few suggestions:

1.) Only one AF stage should be enough for this

2.) The problem with this setup is that it can't produce wideband FM,
usable at the RM radio band (75KHz swing).

3.) The second problem is that to produce UHF signal with this method
you require a large number of multiplying stages which will need to be
aligned (tuned). Alignment can be very touchy mechanically and a fall
on the floor can de-tune the trimmers. It is not a very practical approach,
but it does work.

4.) Another problem with a large number of amplifier stages is that
a intermediate signal can feed through to the output stage. This makes
the usual filtering with LPF unpossible (since signal is under the carrier
in frequency).

Other than that, it can be made to work for NBFM applications nicely.

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Thu Oct 23, 2003 7:04 pm View user's profile Send private message Visit poster's website
pcs
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Post Reply with quote
Otherwise, your website is really cool. Feel free to contact me with any ideas or questions at any time (use email). We might even find a way to colaborate in some way some day.

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Fri Oct 24, 2003 10:52 am View user's profile Send private message Visit poster's website
mildex
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Joined: 21 Oct 2003
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Post Reply with quote
Hi,

This VHF transmitter author, as well as mentioned website owner is Daniel Norman. I just showed his transmitter as an example.

mildex

pcs wrote:
Otherwise, your website is really cool. Feel free to contact me with any ideas or questions at any time (use email). We might even find a way to colaborate in some way some day.

Sat Oct 25, 2003 6:47 pm View user's profile Send private message
pcs
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Post Reply with quote
Ah, it is not you? It sounded as if it was you from your post.

Never mind.

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Sat Oct 25, 2003 7:33 pm View user's profile Send private message Visit poster's website
mildex
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Joined: 21 Oct 2003
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Post Reply with quote
Hi,
could you accomplish this your suggestions into improved schematic of this transmitter(for 400MHz) and make it available?

mildex

pcs wrote:
Hi!

Thanks for the schematic, I'll add it to our schematic section.

I have a few suggestions:

1.) Only one AF stage should be enough for this

2.) The problem with this setup is that it can't produce wideband FM,
usable at the RM radio band (75KHz swing).

3.) The second problem is that to produce UHF signal with this method
you require a large number of multiplying stages which will need to be
aligned (tuned). Alignment can be very touchy mechanically and a fall
on the floor can de-tune the trimmers. It is not a very practical approach,
but it does work.

4.) Another problem with a large number of amplifier stages is that
a intermediate signal can feed through to the output stage. This makes
the usual filtering with LPF unpossible (since signal is under the carrier
in frequency).

Other than that, it can be made to work for NBFM applications nicely.

Tue Oct 28, 2003 7:33 pm View user's profile Send private message
pcs
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Joined: 18 Jan 2002
Posts: 3063
Location: Radio Land

Post Reply with quote
Unfortunately I do not have time right now, perhaps some day.

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Tue Oct 28, 2003 7:47 pm View user's profile Send private message Visit poster's website
evil_genius
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Joined: 10 Feb 2006
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Location: western australia

Post Reply with quote
What would i have to change on the transmitter at
http://hem.passagen.se/communication/buggtx.html
to transmit at the 2.4 ghz range.

my goal is to make a bug i can use about 50 +\- meters
Sat Feb 11, 2006 12:37 pm View user's profile Send private message MSN Messenger
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