Yaesu FRG-7 anntenna selection

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KEWB-N1EXA

Acushnet Heights Radio 740
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Great videos! Great find and fix! After ironing out all of those wrinkles how have you liked it?
The Chinese One here on the video I ended up selling on Ebay and Went with the Noo Smart SDR and Up Converter
which I found to be more Frequency Stable and the Up Converter has a great HF front end over the striaght Q input SDR.

The Vanilla Chinese SDR was a good learning Test Bed- They Still go for $20-25 on Ebay. But how many people Gave up when it didnt work
on HF ! The HF circuit was ok but I thought is picked up to much noise and had a very open front end prone to overloading which i found to be a major draw back even with an AM broadcast band TRAP the local AM station did a job on HF with overloading. a strong US station on HF
would just wipe out the 40 meter band too.

Here is the Noo Smart SDR. - These are a far better Product - Very Stable saw Version 4.0 has more bandwidth but cost $50+
Below is version 2 Which I have a few. They need a heat sink because they get warm.



HDSDR Software



Pete N1EXA
 
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KEWB-N1EXA

Acushnet Heights Radio 740
Joined
Jan 1, 2020
Messages
416
Yeah the challenge and the grandeur of the accomplishment just kind of dissapears at that point. Rather than climb the mountain just take the tram 😆 Then the other aspect is if technology collapses it's nice to have something that's easy to repair and tried and true... but that's another matter entirely 🙄

I've read good things about SDRplay and was leaning that direction but I haven't completely decided and I'm open to suggestions. They're out of stock until March and I'm not trying to pay $350 through HRO. I'm all about learning hard lessons vicariously through others so if you have any advice for me in all ears.
I looked up the SDRplay...
Wow that does allot...Kinda like buying a Bass Boat And GMC Truck when a box of Fish sticks will make the kids happy!
$350 WOW.

Would Like to see one though.
It like the HACK 1 SDR....Would like to try before buying..

Pete N1EXA
 

Champo

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May 4, 2021
Messages
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I looked up the SDRplay...
Wow that does allot...Kinda like buying a Bass Boat And GMC Truck when a box of Fish sticks will make the kids happy!
$350 WOW.

Would Like to see one though.
It like the HACK 1 SDR....Would like to try before buying..

Pete N1EXA
I take that back. If you buy the RSP1A directly from SDRplay the RSP1A will run you $145 shipped but they're back ordered. HRO has it for $139.95 shipped but also back ordered. I swear that two weeks ago it was ~$300 from HRO. Strange. It isn't a drop in the bucket by any means but it's a lot better than $300 lol.
 

majoco

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In answer to your first post about the FRG7.......

You can see from the diagram below that if you have a wire antenna connected to the "BC" terminal, it is only connected to the input preselector when band"A" is selected. You can also connect a wire antenna to the "SW2" which is joined to the coax socket. Now many receivers have this arrangement and what most instructions say that if you have only the coax socket connected, then put a jumper across the SW2 and BC terminals. My Frog 7 goes very well, but it's not in the top flight and it was never intended to be - once you get the hang of it - you need three hands - it'll work for you too. Remember - a radio is only as good as it's antenna.

frg-7-circuit-diagram-1 clip.jpg
 

Champo

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Thank you very much! That info is very helpful. Hypothetically speaking, if you had a long wire antenna connected to the SW2 position and a band specific antenna connected to the coax connector, I would presume that the receiver would be "hearing" both antennas at the same time and bringing in the best signal from the more efficient antenna but at the same time bringing in the noise level from the noisier antenna? If the above is true it would seem only having one antenna connected at a time would be the best option depending on the circumstances.
 

majoco

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I would presume that the receiver would be "hearing" both antennas

No, it won't. You can see that the band switch when set to "A", the BC band 500kHz to I.6MHZ is connected to the BC socket and the signal goes around the attenuator to the BC band pre-selector terminal "A". If any other band is selected then the SW antenna or the coax is connected. If you connect two antennas together there's no telling what they will do - at some frequencies the signal might add and others may subtract - sometimes there will be a phase difference as the signals travel via different path lengths and produce all sorts of weird effects. Best to have the right antenna for the band - a long wire for the BC band and a dipole (look up 'Off centre fed dipole') for the SW bands and plug them into the BC and SW sockets. Better still for an OCFD, a balun up at the antenna and coax to the coax socket.
 

Champo

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That makes sense. Thank you for the correction and excellent explanation. I have enough wire to make an 80 meter receive only loop and a 9:1 balun. I was considering going that route. I would appreciate your thoughts. The reason behind my question is I'm running an Ameco PT preamplifier with a Yaesu FT-101E. The Ameco has a coax receiver connection that allows you to piggy back a receiver off of the same antenna that the FT-101E is using. This will probably be how I'm going to run the FRG-7 but i wanted to confirm the FRG-7's antenna setup in case I decide against. Your reply is greatly appreciated.
 

Boombox

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Just pull the antenna from the back of the radio and "switch" it that way. Problem solved. If you're in a region where there are lightning storms, you're probably going to be using an external switch or grounding the antenna when not in use, anyway.

Otherwise, yes, if you have a SW wire connected to the clip terminal and another one connected via coax, the radio will 'see' both wires.

But like I said, just disconnect the antenna you're not using at the time.

And FRG-7's work well with various amounts of wire. I used mine on 80 ft. wire, a V-beam, and a 150 ft low wire (that one primarily for MW). The radio worked fine on all of them.
 
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