Please let me know if this is a dumb project idea...

[WSGI647]

This is an emergency use case and not really practical but...

Line of sight is a major factor with GMRS so that being said, would it be feasible to have a helium balloon with a light weight repeater payload attached to a fishing rod and line to reel it back in?

You would have direct, unobstructed line of sight to the balloon repeater and it, being as high up as you have fishing line, would have line of sight extremely far.

Maybe in the kit have a one time use sized helium container for portability and to be a bit more practical? Obviously this isn't something you'd go out and do every day, but it would be an extremely useful kit to have in a vehicle that may get stranded without cell service or signal to connect to a repeater. Even just using simplex, this could be a life saver, right?

[WRTC928]

It's an intriguing thought. From a technical standpoint, it should work. The issue would be in practical application How big a balloon would it take to lift a practical repeater? Batteries are heavy. How much use can you get out of a repeater before the battery went out? Probably the only way to know is to try it and see. 

[Hoppyjr]

Not sure where you live, but my experience has been when power goes out it’s due to major storm conditions. Not exactly the ideal time to be launching a balloon, or expecting to retrieve it.

[SteveShannon]

23 minutes ago, WSGI647 said:

This is an emergency use case and not really practical but...

Line of sight is a major factor with GMRS so that being said, would it be feasible to have a helium balloon with a light weight repeater payload attached to a fishing rod and line to reel it back in?

You would have direct, unobstructed line of sight to the balloon repeater and it, being as high up as you have fishing line, would have line of sight extremely far.

Maybe in the kit have a one time use sized helium container for portability and to be a bit more practical? Obviously this isn't something you'd go out and do every day, but it would be an extremely useful kit to have in a vehicle that may get stranded without cell service or signal to connect to a repeater. Even just using simplex, this could be a life saver, right?

I could see that being done using hardware similar to a DMR hotspot.  It would be very low power and capable of running for a long time on a lightweight LiFePO4 battery. 
It would be fun to try, anyway. 

[WRYZ926]

Weight would be the main issue due to batteries. While LifePO4 batteries are pretty light, that is still weight that you need to account for. A single 10 AH LifePO4 battery weighs 2.25 pounds on average. My Redodo 100AH LifePO4 battery is 24 pounds.

[SteveShannon]

2 hours ago, WRYZ926 said:

Weight would be the main issue due to batteries. While LifePO4 batteries are pretty light, that is still weight that you need to account for. A single 10 AH LifePO4 battery weighs 2.25 pounds on average. My Redodo 100AH LifePO4 battery is 24 pounds.

I’d never use a battery that big for a 100 mw repeater intended to fly in a balloon for a short time in emergency situations. I’d use something like an 1800 mah battery. 

[WRYZ926]

I guess I misunderstood things. I was thinking of trying to run a repeater for several hours and I don't see an 1800 mah battery lasting very long if the repeater sees a bit of use.

[SteveShannon]

44 minutes ago, WRYZ926 said:

I guess I misunderstood things. I was thinking of trying to run a repeater for several hours and I don't see an 1800 mah battery lasting very long if the repeater sees a bit of use.

Based on the scope described in the original post I understand that this would be strictly emergency, which implies short duration. People wouldn’t be chatting on it.  If it were me I’d do an APRS beacon with a canned message rather than a repeater, but it could simply be a simplex repeater. 

[WRYZ926]

8 minutes ago, SteveShannon said:

 If it were me I’d do an APRS beacon with a canned message rather than a repeater, but it could simply be a simplex repeater. 

I agree with using an APRS beacon instead.

[LeoG]

Nice out of the box thinking.

[WRCR724]

On 1/4/2025 at 1:30 PM, WSGI647 said:

This is an emergency use case and not really practical but...

Line of sight is a major factor with GMRS so that being said, would it be feasible to have a helium balloon with a light weight repeater payload attached to a fishing rod and line to reel it back in?

You would have direct, unobstructed line of sight to the balloon repeater and it, being as high up as you have fishing line, would have line of sight extremely far.

Maybe in the kit have a one time use sized helium container for portability and to be a bit more practical? Obviously this isn't something you'd go out and do every day, but it would be an extremely useful kit to have in a vehicle that may get stranded without cell service or signal to connect to a repeater. Even just using simplex, this could be a life saver, right?

I say give it a try before you actually need to rely on this method in an emergency.

Would make for an interesting YouTube video too. Let us know once you have the video published!

 

[WRUU653]

This idea brings all kinds of ideas to mind. An HT that has cross band repeat tied to balloons or maybe depending on how high the balloons go how about an HT with Bluetooth connection?    
Interesting ideas that could be fun to test. My question would be how likely are you to have helium at the ready for an emergency? Still I’d be interested in seeing this tested. 

[WRCR724]

2 minutes ago, WRUU653 said:

My question would be how likely are you to have helium at the ready for an emergency? Still I’d be interested in seeing this tested. 

You don't have helium in your go kit? 

[WRUU653]

1 minute ago, WRCR724 said:

You don't have helium in your go kit? 

I used it all up making high voices.

[LeoG]

Old school heat balloon.

[tweiss3]

You do have to keep in mind lighting requirements over 200' AGL I believe, that is FAA safety.

[SteveShannon]

4 minutes ago, tweiss3 said:

You do have to keep in mind lighting requirements over 200' AGL I believe, that is FAA safety.

It’s also subject to the scope conditions and requirements of FAR 101 for moored balloons. 
https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F/part-101

[RIPPER238]

Interesting. I would think finding the tallest tree on the tallest mountain would be ideal. But i can see putting a KG10H in repeater mode and launching it up with a balloon would work for a while. Longer flights would require a solar panel and bigger balloon.