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Messages - TickingMind

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1
FM Free Radio / CZE-7c for broadcasting
« on: May 02, 2020, 1355 UTC »
My wife and I have been travelling to Haiti for the past few years and while we are stuck at home with COVID warnings, no flights, I was asked by a minister in Haiti via email about a transmitter they use, A CZE-7C, however the antenna and cable were stolen or vandalized (not too sure).

They were using a folded dipole and the range was perhaps a few miles, enough to cover a village. I suggested a coax colinear which could just be housed in PVC pipe (Salt air is not very nice). However, the antenna that I planned would use 75ohm RG6 rather than RG58 which is very hard to get. Is there a substantial difference with tolerances for those who are familiar with this transmitter (50 to 75ohm?)

Many thanks

2
Sometimes it takes another read of the verbiage to catch things that may not seem just right.
Example is as follows:

B.2 Band 510-1705 kHz
Devices using this band shall comply with one of the following requirements:

The total input power to the final radio frequency stage shall not exceed 100 mW, and the total length of transmission line, antenna and ground lead (if used) shall not exceed 3 m.
The field strength of radiated emissions shall not exceed 250 µV/m measured at 30 m
Transmitters that employ a leaky coaxial cable as a radiating antenna may meet the field strength limit of 15 µV/m, as measured at a distance of 47715/(frequency in kHz) m (equivalent to wavelength/2π) from the coaxial cable.
Emissions outside of this band shall be attenuated by at least 20 dB below the mean transmitter output power, or to the general field strength limits specified in RSS-Gen, whichever is less stringent.

So you read through the actual wording that the Canadian government has posted.
Notice something?

"One of the following" is clearly stated. Not "All" but "one of the following"

To ones advantage, I don't know - But it makes you think that loopholes might exist elsewhere.

TM.

3
You are welcome to discuss the frequency pulling question on this thread. It is all connected :)

I moved PVC to a new temporary frequency using the generator. It is a simple switch press on the transmitter to go back to the crystal at 13,558.4 kHz

Prizes for correct answers to "What frequency is PVC on today"

Cheers

Ed

Very weak but I started to hear some chirps on 13,563.760. Never noticed them before, a little too weak to make anything out (yet) but keeping the decoder on it when not watching. Maybe it's you????  ;)

4
How far has one been able to pull a Black Cat 22m beacon (and how?)
I've been able to pull it up slightly, but it seems as to be expected the addition of caps brings the freq down into the QRM zone.
Perhaps a thread for another discussion but found it fitted in some way / context.
The Ultimate 3 I have is obviously not an issue, but as previously mentioned in this thread, crystal controlled devices seem to be clustered.
Would be interesting to hear other thoughts on this

Jason AKA TickingMind
Beacon J1LPB

5
22 Meter Band HiFER Beacons / Re: antenna update
« on: September 05, 2018, 0253 UTC »
I sometimes notice that morning and evening moisture / dew often attribute to the change in readings, if that is of any help. But that can also mean that you might have a point where you are exposed and may be seeing a slight short across the output terminals /connection point or somewhere along the line.

I am sure you will source the problem out and fix it up! :)

TM

6
22 Meter Band HiFER Beacons / J1LPB Beacon Southern Ontario, Canada
« on: September 05, 2018, 0215 UTC »
Good evening folks;
J1LPB Beacon has been on the air now for a number of days, TX is 13.555.410 with a rotation of WSPR, QRSS3 and CW.
Gridzone FN03

This is a Ultimate 3s unit, driving a homebew "Beta" KGD short copper dipole (Vertical orientation, horizontal did not work out as well as anticipated - but more to experiment with).
Device is running 24/7 - WSPR and QRSS have been heard and acknowledged, fantastic - Hoping for some CW reports when the conditions are right.

TickingMind A.K.A Jason
J1LPB

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