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Non-typical repeater application.
- Thread starter radiolearner
- Start date
@brandon7861
just ordered two more yagi's and another btech amp.
Hopefully that will help get me from A to X to G.
(Two of the yagi's are vhf; one is uhf. The 2nd btech amp is uhf.)
just ordered two more yagi's and another btech amp.
Hopefully that will help get me from A to X to G.
(Two of the yagi's are vhf; one is uhf. The 2nd btech amp is uhf.)
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I put X where I did to utilize line of sight, you shouldn't need an amp for that...
The ebay cable just arrived. I am having some success with it for connecting two baofeng uv5R's together. I am not presently programming any offsets. I have four radios, two set at 146mhz (radios 1 and 2) and two set at 445mhz (radios 3 and 4). Two of the four radios (call them 2 and 3) are connected by the cable, with Vox set to 10 on the 445mhz one of the pair.
At least within my house, I was able to communicate to radio 4 with radio 1 with the transmission silently going through radios 2 and 3.
A step in the right direction.
----If the above is an invalid setup for actual application, please let me know.
At least within my house, I was able to communicate to radio 4 with radio 1 with the transmission silently going through radios 2 and 3.
A step in the right direction.
----If the above is an invalid setup for actual application, please let me know.
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Do I need a "duplexer" for this to work well ?The ebay cable just arrived. I am having some success with it for connecting two baofeng uv5R's together. I am not presently programming any offsets. I have four radios, two set at 146mhz (radios 1 and 2) and two set at 445mhz (radios 3 and 4). Two of the four radios (call them 2 and 3) are connected by the cable, with Vox set to 10 on the 445mhz one of the pair.
At least within my house, I was able to communicate to radio 4 with radio 1 with the transmission silently going through radios 2 and 3.
A step in the right direction.
----If the above is an invalid setup for actual application, please let me know.
Depends on the situation:
If you were connecting two radios to the same antenna and those two radios were in the same band only separated by a few MHz, then yes, you would want a duplexer.
If you were connecting two radios in different bands to the same antenna, you would want a diplexer.
If you are running each radio on its own, you don't need a diplexer or a duplexer. The trick is to keep the antennas of the two radios separated by some distance, preferably having the two antennas share the same axis (vertical separation of vertical antennas) so the antenna of one radio is in the null of the other antennas pattern.
The only issue I see is that you are using the 2m and 70cm band, and by doing so, you might end up with desensitization of the 70cm receiver being it is the third harmonic of 2m. What that means is that wherever you put the repeater radio pair, that pair should receive on 2m and transmit on 70cm, because if you did it the other way around, the 2m transmission that close to the 70cm radio might interfere with it's reception as soon at it transmits. From your description above, you have that backwards...
Edit: Another issue you might have is the audio cable linking the radios picking up RF. If they misbehave, suspect this and consider a ferrite that is rated for RFI on the transmitting frequency on that audio cable.
If you were connecting two radios to the same antenna and those two radios were in the same band only separated by a few MHz, then yes, you would want a duplexer.
If you were connecting two radios in different bands to the same antenna, you would want a diplexer.
If you are running each radio on its own, you don't need a diplexer or a duplexer. The trick is to keep the antennas of the two radios separated by some distance, preferably having the two antennas share the same axis (vertical separation of vertical antennas) so the antenna of one radio is in the null of the other antennas pattern.
The only issue I see is that you are using the 2m and 70cm band, and by doing so, you might end up with desensitization of the 70cm receiver being it is the third harmonic of 2m. What that means is that wherever you put the repeater radio pair, that pair should receive on 2m and transmit on 70cm, because if you did it the other way around, the 2m transmission that close to the 70cm radio might interfere with it's reception as soon at it transmits. From your description above, you have that backwards...
Edit: Another issue you might have is the audio cable linking the radios picking up RF. If they misbehave, suspect this and consider a ferrite that is rated for RFI on the transmitting frequency on that audio cable.
Are you sure the transmitter is even working correctly? Is there some local interference?
I would start with making sure the transmitter is putting out the rated power, the antenna system is good, and its on frequency.
Stinging bofangs together in some sort of rube goldberg fashion would just be something that needs constant fiddling with. On your drawing you shouldn't need that to go from A to B.
Nope, I have 70+ ft granite hills between transmitter and receiver. At 375 yards I would look at issues with your transmitter and/or antenna. That distance should be no problem for the DA transmitter. 30 ft. dirt mounts would easily knife edge refract a VHF signal to the other side. The simplest solution is to use an external antenna and get it as high as possible but I would check to see if the transmitter is actually transmitting full strength. I was a DA dealer for almost a decade and once in a while a transmitter would be faulty and have a much reduced range.
This one seems to have good reviews. amazon link
Amazon product ASIN B01D86IKIQ
Looks like it would at least get you in the ball park with power, freq, and swr.
A free thing you could do first is put your bofangs the same freq and with a helper go to the different points and see if you can talk to each other. If you can then you know there is something up with the alarm's transmitter. If you can't talk between points A and B then there is something else going on.
Great thanks. Gonna give that a try.
What I have been doing is to use a voice-recorder on my smartphone so that I can "be at two places at the same time". (I sync the app's timer up with my stop watch so that I know what I should hear when, when I play it back.)
GREAT NEWS: Amplifying the MURS MAP's radio output with the amp and the yagi is giving me alerts on all needed locations. I did not do any repeating. I just used a single 2meter frequency and a simple "rubber duck" on the receiving end. It was all about the POWER. The MURS MAP was just simply too wimpy to get the job done by itself. I tested several of the hardest locations, while the receiver-radio was inside my vehicle (on the seat) to make it even harder. The yagi was on a 6ft pole I stuck in the ground; the bottom half was steel; the top half aluminum.
Now I need to solve the part-b of the problem -- I need to make the system tamper-proof. Right now, anyone could just turn the power supply off, turn either of the radios off e.g., and just drive the vehicle right through....and I would never get alerted (suggestions welcome while I work on it ).
Equipment used, with links reproduced below for convenience:
1.cable (connects Dakota radio to uv-5R with uv-5R set to vox-1, squelch 5.).
2.amp
3.yagi antenna
4.power supply / adapter
1.Kework 2-Pack 11.8 inch Mini Coiled 3.5mm to 2.5mm Audio Cable, 90 Degree 1/8" 3.5mm TRS Jack Male to 2.5mm TRS Jack Male Stereo Audio Aux Coiled Cord (3.5mm to 2.5mm)
2.BTECH AMP-V25 VHF Analog Amplifier
3.A144S5 A144-S5 Original Diamond Antenna Base Station Yagi Beam - 144-148 MHz 5 Element 9dBi
4.Portable 12v power-supply:
Amazon product ASIN B09X2HR6FPplug-in adapter box:
and of course the cables to connect the uv-5R to the amp and the amp to the antenna.
Maybe this should be a sticky. : p
GREAT THANKS FOR ALL THE HELPS.
Now I need to solve the part-b of the problem -- I need to make the system tamper-proof. Right now, anyone could just turn the power supply off, turn either of the radios off e.g., and just drive the vehicle right through....and I would never get alerted (suggestions welcome while I work on it
).Equipment used, with links reproduced below for convenience:
1.cable (connects Dakota radio to uv-5R with uv-5R set to vox-1, squelch 5.).
2.amp
3.yagi antenna
4.power supply / adapter
1.Kework 2-Pack 11.8 inch Mini Coiled 3.5mm to 2.5mm Audio Cable, 90 Degree 1/8" 3.5mm TRS Jack Male to 2.5mm TRS Jack Male Stereo Audio Aux Coiled Cord (3.5mm to 2.5mm)
2.BTECH AMP-V25 VHF Analog Amplifier
3.A144S5 A144-S5 Original Diamond Antenna Base Station Yagi Beam - 144-148 MHz 5 Element 9dBi
4.Portable 12v power-supply:
Amazon product ASIN B09X2HR6FPplug-in adapter box:
Universal Compact Bench Power Supply - 9 Amp Regulated Home Lab Benchtop AC-DC Converter Power Supply for CB Radio, HAM w/ 13.8 Volt DC 115/230V AC Switchable, USB, Cigarette Lighter - Pyramid PSV90
Amazon product ASIN B07P9RQVRD(The pyramid is AC-driven and plugs into the front of the power-supply.)and of course the cables to connect the uv-5R to the amp and the amp to the antenna.
Maybe this should be a sticky. : p
GREAT THANKS FOR ALL THE HELPS.
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