lostbaka

Some radio questions

8 posts in this topic

I think I can divide these up into meaningful groups:

Mobile rigs and RF power:

So the 817ND and 857D get great reviews. Both are HF/50m 6m, VHF, UHF and mobile but one is a QRP rig so:

1) Is 5W enough? - I'm interests are leaning toward packet and sats (heck pacsats seem like the best of everything)

2) Are their down sides to RF amps especially for VHF and higher?

3) Why not turn medium power mobile radios into backpack setups? Aside from from the fact radios like the 857 aren't designed for low current consumption, why not run off lithium battery packs? Can't the transmit power be reduced on the radio?

ISM bands and Packet:

4) Can anybody experiment on the ISM bands or is it just licensed hams?

5) Is there a high interest in VHF+ packet operation? I never hear anyone talk about it on the local repeaters but I've been listening to consistent activity on 145.07 from where I am in CT

Satellites:

This topic has come a few times in this section and I still say it's interesting stuff:

6) Stemming from Boxboro\ECRV post - Why use satellite comms and IP telephony for emergency communication? I would think that's not rugged enough for that

7) Any point in parting out the Dish Network \ DirectTV receivers that always make their way to Goodwill \ Salvation Army?

8) *This could go under the mobile section* Anyone use a transverter with mobile or handheld?

kinda a lot i know, any help would be appreciated

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Anyone can experiment in the standard ISM bands (900 MHz, 2.4 GHz, 5.8 GHz, etc.) using the FCC Part 15 rules, which restrict RF power output.

Hams can also use these bands if they stay in the proper frequency ranges and operate under FCC Part 97 rules, which allow more RF power, but restrict content and encryption use. You'll still need to I.D. every ten minutes.

The ARRL website should have all the nitty-gritty details on that.

Amateur packet is very inactive right now, but there are still a few people out there trying to tweak Part 15 off-the-shelf hardware for higher performance in the ham bands.

AeroComm CL4490 Experiments:

http://www.qsl.net/n9zia/aerocomm/

ID'ing via ICMP Echo Request Packets:

http://www.qsl.net/n9zia/pingid.html

Using Part 15 Wireless Ethernet Devices For Amateur Radio:

http://www.qsl.net/kb9mwr/projects/wireless/plan.html

Modifying Consumer Off the Shelf Wireless LAN devices for Specialized Amateur Use:

http://www.qsl.net/kb9mwr/projects/wireless/modify.html

Amateur Radio Allocations and Overlapping Part 15 Bands - An Overview and a Part 97 Versus Part 15 and Permissible Power Comparison:

http://www.qsl.net/kb9mwr/projects/wireless/allocations.html

Edited by gbppr
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It's good hear packet isn't completely dead. I kinda got the same impression when I asked John Hansen ( creator of 1200 bps TNC-X, http://www.tnc-x.com/ ) about the popularity of 9600 bps networks.

Another somewhat random question. Hams have been converting surplus Motorolla commercial gear for some time now. Does this also mean Moto data radios\modems have been getting the same treatment?

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I think I can divide these up into meaningful groups:

Mobile rigs and RF power:

So the 817ND and 857D get great reviews. Both are HF/50m 6m, VHF, UHF and mobile but one is a QRP rig so:

1) Is 5W enough? - I'm interests are leaning toward packet and sats (heck pacsats seem like the best of everything)

2) Are their down sides to RF amps especially for VHF and higher?

3) Why not turn medium power mobile radios into backpack setups? Aside from from the fact radios like the 857 aren't designed for low current consumption, why not run off lithium battery packs? Can't the transmit power be reduced on the radio?

ISM bands and Packet:

4) Can anybody experiment on the ISM bands or is it just licensed hams?

5) Is there a high interest in VHF+ packet operation? I never hear anyone talk about it on the local repeaters but I've been listening to consistent activity on 145.07 from where I am in CT

Satellites:

This topic has come a few times in this section and I still say it's interesting stuff:

6) Stemming from Boxboro\ECRV post - Why use satellite comms and IP telephony for emergency communication? I would think that's not rugged enough for that

7) Any point in parting out the Dish Network \ DirectTV receivers that always make their way to Goodwill \ Salvation Army?

8) *This could go under the mobile section* Anyone use a transverter with mobile or handheld?

kinda a lot i know, any help would be appreciated

The 817 carries on the tradition by Yaesu that made radios like the FT-7. QRP (less than 10w operation) is actually pretty fun. It shows that you don't need to run 50-1500 watts to talk around the world. You can take any 12v radio and turn it into a backpack rig. The trick is using good antennas with plenty of gain. Gain will get you farther than power (because you get the boost in both receive and transmit, not just transmit like many alligators out there). Amps again are good for pushing your signal... but not good for receiving signal. I'd only consider an amp *AFTER* i've done all I can with my antenna configuration (including switching antennas).

You'd really want a dual band transceiver when you operate satellites. Part of operation is being able to hear your own downlink. You can't do that with radios that only listen to one band at a time.

There is a bunch of hams experimenting with ISM 900mhz/1.2 and 2.4ghz (and more). In fact, I've been on the hunt to find a 2.4 to 1.2ghz transverter so I can bounce a wifi signal through AO-51 in mode L/S.

Packet isn't as big as it used to be. APRS has done much to keep packets flying. But yeah, there's alot of packet on satellites and in Europe especially.

You know, I see those DirecTV receivers all the time. The problem with them is that they don't have the interfaces to really hack them. The smartcard that operates them changes from time to time as well. And it's just a receiver... not a transmitter. It's *much* easier to get a FTA box and hack it. They're made for it.

There are many reasons to use Satellites/IP for emergency comms. Satellite passes are predictable. Satellite passes only require good visibility of the sky and isn't limited by terrain or the ionosphere skip. IP means it's instantly interfacable to modern computer networks for interoperability which is mad useful in a situation where you need to build emergency networks in short order between different organizations.

And yes, I've used both. Currently HT's but I'm shopping for yet another mobile that fits my new operation scheme.

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It's good hear packet isn't completely dead. I kinda got the same impression when I asked John Hansen ( creator of 1200 bps TNC-X, http://www.tnc-x.com/ ) about the popularity of 9600 bps networks.

Another somewhat random question. Hams have been converting surplus Motorolla commercial gear for some time now. Does this also mean Moto data radios\modems have been getting the same treatment?

Some have modded Motorola Data Radio/Modems. But they're not designed for ham bands. So it takes some doing to move them over. Not illegal to use them on ham bands either as long as you identify with morse or a voice id or post the modems you use on the internet under your callsign (because people must be able to decode your transmissions (within reason).

*unlike D-STAR but that's another argument*

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You'd really want a dual band transceiver when you operate satellites. Part of operation is being able to hear your own downlink. You can't do that with radios that only listen to one band at a time.

Alternatively, you could use two single-band transceivers. ;)

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You'd really want a dual band transceiver when you operate satellites. Part of operation is being able to hear your own downlink. You can't do that with radios that only listen to one band at a time.

Alternatively, you could use two single-band transceivers. ;)

Fo sho! :)

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I love my FT-817 and New England has their own QRP club that's very active: http://newenglandqrp.org/

Likewise VHF/UHF+ weak signal is also popular in our neck of the woods: http://www.newsvhf.com/

You can do both of those with an FT-817. It is probably one of the more versatile rigs out there.

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