looking for HF Freqs

[scannerhead3]

i have an icom ic-r3 and i was wondering if anyone had any freqs for planes or ships that i would be able to pick up on it. the only thing is that it doesn't montior SSB. i have heard many shortwave radio stations but i'm more interested in hearing ships are areonautical stuff.

 

[ka3jjz]

Unfortunately you hit your own nail on the head. The R3 won't cover SSB, so you're not going to have much success hearing ships at sea or most any Aero stuff. There are a few Volmets (comes from 2 French words, literally meaning 'flying weather' - think of NOAA 162 mhz on HF...) on AM...

Time to think about an upgrade 73s Mike

 

[Al42]

Unfortunately you hit your own nail on the head. The R3 won't cover SSB, so you're not going to have much success hearing ships at sea or most any Aero stuff. ...

Time to think about an upgrade

Or an external BFO.

 

[SAR923]

All the major VOLMET's are also on SSB. I think there might be a few still on AM in Russia but that's about it. With all the advances in airline communications, I wonder how much longer the VOLMET stations will still be around. I've always been something of a weather nut and the main reason I got into shortwave (with my Hallicrafters Sky Buddy, which will give you some idea how long ago this was ) was to able to listen to VOLMET stations, which were all on AM then. I can still remember how fascinating it was to sit in my basement in Cleveland and hear the current weather in Honolulu. I get the same information in seconds on the net now but it's not quite the same.

 

[scannerhead3]

whats an external BFO

 

[Al42]

whats an external BFO

A little oscillator (signal generator) that's tunable over a few KHz, and is centered at the IF frequency (or last IF frequency, in the case of multiple conversion) receiver. That's the only difference betweenl a SSB-capable receiver and one that isn't - the one that is has a bfo (beat frequency oscillator) built in.

Actually it doesn't even have to be tunable - if your receiver's last IF is, say, 455 KHz, you just put a 455 KHz signal near it (it should sound like you're tuned to a dead carrier, regardless of the frequency you set the scanner to) and tune in a SSB signal until it sounds like normal speech. Most receivers that don't have bfos built in have wide enough IFs that you don't really have to tune the bfo. (The receiver has to be tunable to do this. If yours is only tunable in 5 KHz or 2.5 KHz steps you need a tunable bfo.)

 

[scannerhead3]

These are the IF's for my r3

AM/FM
1st---240.1
2nd---26.05
3rd---0.450

Which one would i use with the BFO

 

[Al42]

Any one would work, but I'd use .450 (450 KHz) - it'll be more stable than 26 MHz.

 

[scannerhead3]

where would i purchase a BFO and about how much would it set me back

 

[Al42]

A bfo isn't really something you buy - it's something you would build. I can't find any 450 KHz oscillator on the web, but if you build any oscillator, crystal or tunable, for 450 KHz, it should work. It would be a transistor (a 2N2222 would work at that frequency) and a few parts - a coil, a few capacitors, a resistor or two, a battery clip and a 9 volt battery - you'd probably want a piece of perf board to build it on, and maybe a little case (Radio Shack 270-283) - probably no more than about $10-$15 at Radio Shack for everything.

 

[Al42]

A bfo isn't really something you buy - it's something you would build. I can't find any 450 KHz oscillator on the web, but if you build any oscillator, crystal or tunable, for 450 KHz, it should work. It would be a transistor (a 2N2222 would work at that frequency) and a few parts - a coil, a few capacitors, a resistor or two, a battery clip and a 9 volt battery - you'd probably want a piece of perf board to build it on, and maybe a little case (Radio Shack 270-283) - probably no more than about $10-$15 at Radio Shack for everything.

 

[scannerhead3]

interesting---i'll have to try it out

 

[scannerhead3]

i went on radioshack.com and was checking out coils, capacitors and resistors---------should i look for a specific kind

 

[kb2vxa]

Hi Scannerhead and all,

After going through the trouble of building a BFO you still have to find a way of injecting it's output into the detector, NOT the IF without upsetting the apple cart. That's a bit beyond the scope of a general discussion and so is operating the receiver with it, so you're best bet is to save your pennies and buy a good communications receiver with a product detector.

No, you don't need the latest and greatest digital DC to light every mode under the sun cost a king's ransom radio. Shop around for a good used general coverage receiver with a product detector, not just a BFO for SSB. The older ham/general coverage receivers, usually tube types really should be avoided by the casual listener, a bit hard to operate and rather expensive since most are collector's items. Something in the middle is what you should shoot for but make sure it's easy to tune in, SSB can give you a lot of grief if the turns per kHz tuning ratio is too little.

 

[scannerhead3]

i was thinking about the icom ic-r20

 

[Al42]

Hi Scannerhead and all,

After going through the trouble of building a BFO you still have to find a way of injecting it's output into the detector, NOT the IF without upsetting the apple cart.

Well, yeah, if you want to be a purist ...

But just sitting the bfo near enough to the receiver that the signal leaks in somewhere will still work. We're not trying for minimum IM here, just enough detection that the signal is understandable.

 

[scannerhead3]

I looked on radio shack.com and didn't find the 2N2222---would the 2N4401 tansistor work

 

[Waldo325mvfd]

USCG air 5.969
air 3.485 weather
8)

 

[kb2vxa]

Hi Scannerhead and all,

The 2N2222 is long obsolete but any small signal transistor will do, just observe the correct polarity and ratings. Well, since you can power it with a single 1.5V AA cell don't worry about the ratings. (;->)

"Well, yeah, if you want to be a purist ... "

It's not a matter of being a purist, there are several technical considerations well beyond the scope of this discussion. I have "been there, done that" with several types of signal injection and they're all very tricky and not worth the price of a receiver with a product detector.

"But just sitting the bfo near enough to the receiver that the signal leaks in somewhere will still work. We're not trying for minimum IM here, just enough detection that the signal is understandable."

Well maybe, again lots of variables to consider like how leaky the IF strip is. A good one won't pick up external signals and won't radiate any as per FCC Part 15.

Close, but no cigar although you accidentally hit on one of my methods. I used to have a 2M Gonset Communicator II with a VFO which I set to "spot" which injects a signal you can use for synchronizing it with the receive. Naturally I used it as a BFO but it was extremely limited, swamped weak signals while not providing enough injection for strong ones. I did have fun with some friends using SSB, they never guessed I was transmitting AM until I told them. That's right those of you who are confused, "zero beat" means no tell-tale heterodyne and SSB is simply AM with the carrier and one sideband removed.

 

[Al42]

The 2N2222 is long obsolete

The Radio Shack 276-2009 is a 2222.

"Well, yeah, if you want to be a purist ... "

It's not a matter of being a purist, there are several technical considerations well beyond the scope of this discussion. I have "been there, done that" with several types of signal injection and they're all very tricky and not worth the price of a receiver with a product detector.

Sounds as if you haven't "been there, done that". Any signal generator at any of the IFs of the receiver, sitting right near the receiver, will inject enough signal to recover audio from a sideband signal. And, unlike most communications receivers, moving the oscillator closer to or further from the scanner gives you a "BFO injection level control".

"But just sitting the bfo near enough to the receiver that the signal leaks in somewhere will still work. We're not trying for minimum IM here, just enough detection that the signal is understandable."

Well maybe, again lots of variables to consider like how leaky the IF strip is. A good one won't pick up external signals

Hello? We're talking about an Icom ic-r3, not some stealth receiver.

and won't radiate any as per FCC Part 15.

Part 15 doesn't require no radiation.