HAM license radio tracking thread?

[sylvie369]

So...

I should get Art's Beeline "package deal", and an Arrow 7-element 440MHz Yagi, and eventually the Arrow attenuator.

I've got a Kenwood THF6A - I'll need an adapter to connect the antenna's BMC to the radio's SMA. Then I'm set, huh?

Not bad. Am I forgetting anything?

 

[bigredbee]

Originally posted by sylvie369
So...

I should get Art's Beeline "package deal", and an Arrow 7-

....

Not bad. Am I forgetting anything?

Except that my name is Greg

(and you can easily make your own antenna terminated with the proper connector if you wish)

 

[troj]

Originally posted by sylvie369
So...

I should get Art's Beeline "package deal", and an Arrow 7-element 440MHz Yagi, and eventually the Arrow attenuator.

I've got a Kenwood THF6A - I'll need an adapter to connect the antenna's BMC to the radio's SMA. Then I'm set, huh?

Not bad. Am I forgetting anything?

That'll do the trick. As Greg said, you can make your own antenna. Me? I took the "buy it instead of make it" route.

BTW, for the adapter, you can either buy an SMA->BNC adapter, or just buy a cable from Mouser (or wherever else you can find one) that has an SMA connector on one end and a BNC connector on the other.

I've got both, and decided the single cable approach was easier.

-Kevin

 

[sylvie369]

Oops...Greg. Sorry.

I'd definitely go with the cable adapter, yes, rather than a rigid straight-through one. I'm using one already with a cartop magnet mount antenna and the HT, but it's not BNC.

I'll buy the first antenna, but I expect to make one as well. There'll probably be a couple radios/antennae, assuming I get the grant I've applied for.

 

[sylvie369]

Hey, I just made my first HF contact, on 40 meters, ironically on the same day that I met the ARRL President at a local Hamfest. Cool stuff, this.

 

[bigredbee]

I just bought a cool kit -- it's a 40/80 meter 'software defined radio' -- uses the PC soundcard to do the majority of the heavy lifting. Best news is the price -- they're only $40 it's called a softrock 40. Search the yahoo groups for more info.

Now I just gotta find the time to build it!

-- Greg, K7RKT

 

[gonogo]

Hey Guys, thanks for the input. One of my club members, a fellow HAM, recommended this site https://members.aol.com/joek0ov/offatten.html
That attenuator from arrow seems nicem, but pricey. There is some good info here it seems about building your own as well as some kits.

I might give this a try. Thanks Jeff!

 

[gregzo]

Originally posted by BigRedBee
Offset attenuators are awesome, but not necessary. Instead, you can just tune your radio off frequency until you can just barely hear the transmitter as you get closer.

I agree with Greg on this. I found a friend's lost Beeline in a hayfield that became detached from its rocket just by de-tuning the frequency. You have to do this slowly and in small increments as you close in on the transmitter. You have to triangulate a bit. We got within a few yards and found it!! I was using an Arrow 5-element yagi.
It was the proverbial needle in a haystack trying to find that little tiny Beeline in a hayfield!!!
Good Luck

 

[troj]

Originally posted by gonogo
Hey Guys, thanks for the input. One of my club members, a fellow HAM, recommended this site https://members.aol.com/joek0ov/offatten.html
That attenuator from arrow seems nicem, but pricey. There is some good info here it seems about building your own as well as some kits.

This does work, but what you may well find is that by the time you're done, you're close to what the Arrow attenuator costs.

A friend and I bought the K0OV attenuators from here for $18 each, and have since discovered that by the time we add an appropriate box ($25 - $30), connectors, etc it's coming close to what Arrow Antenna charges for theirs.

Now, that said, assembling something isn't bad -- you can learn something along the way. But, you won't save a whole lot of money in doing so.

-Kevin

 

[jcsalem]

<b>RE: Detuning vs. Attenuator</b>
I find the detuning method suggested by Greg (the BRB himself) works great. Using it I'm able to get great directionality until I'm nearly on top of the transmitter. I much prefer this to carrying around yet another piece of equipment.

<b>Detuning Tips</b>
Change the tuning step on your HT (aka radio) to the smallest increment. Use the S-meter to measure the signal strength. Once I get close, I tend to open the squelch and detune until the signal barely registers on the S-meter. At that point, I generally can't hear the signal and rely on the S-meter alone.

When I get really close, I'll detach the antenna entirely. After doing this, I can usually tell when I'm within 10 feet or so. This latter technique worked great last year when my BT-60 rocket was lost in a field of chest-high brush. Triangulation also works well when you get close.

<b>Homemade Antenna Experiences</b>
I followed the directions on the 6 element yagi web site using wood as the boom. I started out using hollow aluminum elements (to save weight), but changed the driven element to the recommended brass once I realized I couldn't solder to aluminum. Hollow aluminum was also too fragile.

<b>Softrock</b>
My Softrock kit is also sitting on my to-be-built pile. I think "Software Defined Radio" (SDR) is the coolest radio technology around. The Softrock basically shifts a portion of the radio spectrum down into the audio range, and lets you do some of the tuning and all of the demodulating in software. Using a Softrock (or similar SDR) and a reasonable sound card, you can build a more sensitive and better quality receiver than you can find in almost any commercial receiver. The best part is that there are a lot of gifted amateurs working on it and it has great free software support.

Jim

 

[gonogo]

Im afraid my Idea of my idea for using a scanner isnt working so well. I cant detune it with much precision so I am forced to build or buy an offset attenuater. I still have some toying to do with it but so far the best I could do at about 300 yards is get about 180 degrees of directionality from my yagi/scanner. Im also afraid that the scanner is offering no sheilding at all alLowing the signal to simply flood the reciever thereby makeing the yagi a moot point.

 

[jcsalem]

I'm sorry to hear the scanner didn't work at close range. I bought a used Yaesu FT-50r handheld transceiver about a year ago for $150 which works great. You should be able to find a similar used HT on eBay. A good, more recent model is the VX-5R.

By default, the tuning step was too high (25kHz) but if you dig into the menus, you can change it to 5kHz which seems to work well.

BTW, to test your "lack of shielding" theory, remove the antenna entirely and see what happens.

Jim

 

[Adam Selene]

I just got my new general license in the mail! 2 weeks from taking the test. amazing considering how busy they must be with everybody upgrading.

 

[sylvie369]

Originally posted by Adam Selene
I just got my new general license in the mail! 2 weeks from taking the test. amazing considering how busy they must be with everybody upgrading.

I was in the database on Monday morning after Saturday testing, both for my Tech in late January and for my General upgrade in late February. Definitely no complaints here.

Man, 40m and 80m were wide open here yesterday evening.

 

[gonogo]

nice job with your license guys.

My scanner will work, its just a matter of fine tuning. I found some other HAMs in my club that have some experiance with foxhunting and such and it seems that an attenuater is not as hard to come bye as I thought. That is one more plus for me and my quest to track on the cheap.

On a side, for those of you wondering as long as it took me to figure out, foxhunting has nothing to do with foxes, hounds, or horsees...LOL. Radio tracking, it seems has been a long time passion of many amature gurus. There is much to know on this subject, enough to distract me from rocketry almost, but....

My mission is to do it cheap, I never said anything about easy.

I do have some work and learning to do before I HAM out all of the details. I do expect success.

 

[rsynoski]

Originally posted by gonogo
Im afraid my Idea of my idea for using a scanner isnt working so well. I cant detune it with much precision so I am forced to build or buy an offset attenuater. I still have some toying to do with it but so far the best I could do at about 300 yards is get about 180 degrees of directionality from my yagi/scanner. Im also afraid that the scanner is offering no sheilding at all alLowing the signal to simply flood the reciever thereby makeing the yagi a moot point.

My experience with my scanner pretty much reflects yours. Additionally, I find that the sensitivity of the scanner is not very good. With a 5 element yagi the range on the ground is about 1/2 mile when using the scanner.

 

[gonogo]

I was directed to good link by a fellow club member. members.aol.com/joek0ov/offatten.html
and I built an attenuator from this page.

I also found some other good sites by google.
www.qsl.net/nz0i/projects/attenuator/attenuator.html
www.rckara.org/content.php?contentID=42&ID=81

These are all good design sites for DIY attenuators. I will follow this with my own pics and experiance. One thing I will stress is that in order to save money do not go to RadioShack, find a good local vendor or online vendor. RS bites. This site https://members.aol.com/homingin/ will lead you to a good source of vendors and I was lucky enough to find one just miles from me that had everything I needed on the cheap.

 

[gonogo]

I know these pics are of low quality but it is what it is. This shows all the parts for the attenuator.

 

[gonogo]

Here everything is soldered together.

 

[gonogo]

Gee, thats out of focus and so is this. From the other side.

 

[gonogo]

the complete package.

 

[gonogo]

That looks nice but does it work? This is the whole package budget project in a bundle.

 

[gonogo]

Say that ten times fast.

Honestly though, I'm having a hard time making this thing work right. I dont know if its the yagi or the attenuator thats causing me problems but I have put a lot of work into both.

At a distance my setup works fine but up close (1/2 to 1/4 mile or less probably) I still am losing direction sense. My attenuator does work, dont get me wrong, it does just what it was desinged to do just to a much lesser degree than I hoped.

I am happy to say I have had some success to this point I will humbley state that now I need help in tying this all together.

 

[FredA]

Sorry to say, that does not look like proper RF wiring techniques.
You are dealing with ~400Mhz RF.
Altimeter-style wiring won't cut it.
You need COAX and 50-Ohm impeadance held reasonably closely in order to get signal though your box.
Also - I'd recommend a metal box or Faraday shield of some flavor.

 

[als57]

You might want to try putting the circuit in an all aluminum box. Hammond makes some suitable boxes. And use small co-ax for the interconnects (like RG-174). This should help get more signal thru.

Also the signal antennuation at 400MHz is signifigant due to loss in the co-ax. So use a good grade of co-ax and keep the lenghts short outside the box.


Al

 

[gonogo]

Al and Fred,

Thankyou for the input. I have been considering what both have mentioned and studied up a little more. I will do a couple things first to try to make this work better.

First, I have purchased an aluminum box to reinstall the circuit. Second, I will shorten the jumpers, going so far as to use just a BNC male-to-male adapter between the box and my scanner. For now though I think I'll stick with a shorter RG58 jumper going to my yagi. Hopefully these to things will make a differance.

I do have some questions though concerning other changes I could make.

Fred, you mentioned the wiring. I have noticed that most designs use this kind of wayward style of wiring and some even use a "dead bug" fashion with leads and parts going just anywhere that they will fit inside a plastic box. I do agree that I can improve by repositioning things on my board so as to keep my leads shorter and to keep some parts away from others such as the diode and the ocillator. My question regards 440Mhz, most of these designs are used for 2m. Does 440Mhz require more consideration due to its higher frequency? There is not alot of info out there regarding tracking on 440Mhz as most foxhunters use it for 2M on the 3rd harmonic.

Al, you said to use RG174 for the interconnects. Did you mean as the the jumpers or for carrying the signal inside the box? RG174 is sub-miniature, about as small as it gets I think. There are two reasons I am using RG58, its supposedly most compatible with BNC connectors and because the shielding is copper its easy to solder.

I appreciate everyones input feeding this thread and I hope it has been helpfull to others with the same interest as me. I do have one more question to cap off this long winded inquirey. I have seen some designs use a wrap coiled in the signal lead as a choke either at the yagi or internally is this something I should incorporate?

 

[als57]

I suggested the RG-174 for inside the box. The RG-58 is fine for the outside connections and is good for the BNC connection. Just be sure to use a good grade of RG58 ; some of the stuff marketed is real junk. Belden cable is usually a good bet. And keep the runs short ; even good RG-58 is lossy at UHF.


Al

 

[FredA]

You want a clean RF path from input through the mixer and out.

To maintain a decent VSWR and low attenuation, you need to keep your impeadance constant at 50-Ohms.

For best performance, you can only do this on a PCB with a ground plane.
Coax will hold the 50-Ohm as long as the shield is intact.
Larger 50-Ohm coax's have lower frequency-dependant losses and/or better shielding.
Make sure you use something rated for >=500Mhz BW and try to use double-sheilded or better.
I'd use the RG6-Quad Shield that I put in my house for cable TV.

Strive to keep the stubs outside the shield to less than 1/4" long.
If you must air-wire, place the mixer between short runs of coax and get in and out of the coax as quick as possible.

I'm not sure about how other devices are wired.
I suggest you look on the web for RF PCB & wiring techniques.

FredA

 

[OARJeepr]

Originally posted by freda
-snip-
I'd use the RG6-Quad Shield that I put in my house for cable TV.

-snip-

FredA

RG-6 and anything for residential cable tv is going to have a 75ohm impedence. Don't know if that's going to be a big deal for this application or not.

 

[Uncrichie]

Mike, keep it simple unless you run into further problems. The fact that you are now going to put this in a metal box you should be fine. Do that first and go from there. I think you'll find the box will stop all your problems. Kurt.