Auto Direction Finder
 

Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work using only
my existing VHF antenna and can't afford to buy something that is marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to find.

Auto Direction Finder
 

Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work using only
my existing VHF antenna and can't afford to buy something that is marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to find.


The Sitex set works great. All you need is audio from a scanner (more
frequency selection than a marine VHF), hook up you antenna as in the
instruction manual and it will ADF just fine. This type of pseudo Doppler ADF
works best in the open ocean where it is VERY accurate. If you are near things
that can reflect signals (mountains, buildings etc) expect some errors.

Auto Direction Finder
 

I think that if you check closer you will find that the 525 uses an
Eight-element Adcock DF antenna in addition to your existing VHF antenna. I
have one and have found it to be reliable and accurate withing the published
specs: +/- 10 degrees. This system does introduce a buzzing sound into your
audio that you may or may not find annoying. In an area with a lot of radio
chatter going on, the buzz gets on my nerves and I will frequently turn the
ADF off. Normally I keep it on.



"William G. Andersen" wrote in message
news:_iJsc.21310$wa.12601@fed1read07...
Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work using only
my existing VHF antenna and can't afford to buy something that is marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to find.

Auto Direction Finder
 

Thanks to both of you for the information. Now, how do I explain yet another
$500 worth of boating toys to my wife (the family financier)?...

"Jerry" wrote in message
...
I think that if you check closer you will find that the 525 uses an
Eight-element Adcock DF antenna in addition to your existing VHF antenna.
I
have one and have found it to be reliable and accurate withing the
published
specs: +/- 10 degrees. This system does introduce a buzzing sound into
your
audio that you may or may not find annoying. In an area with a lot of
radio
chatter going on, the buzz gets on my nerves and I will frequently turn
the
ADF off. Normally I keep it on.



"William G. Andersen" wrote in message
news:_iJsc.21310$wa.12601@fed1read07...
Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work using
only
my existing VHF antenna and can't afford to buy something that is
marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to find.

Auto Direction Finder
 

It works great and I agree, a scanner is better than using your VHF radio.
Customers we have sold them to don't like the DF scan (antenna switching)
tone in the audio. It must be there to give the DF unit a bearing reference.
Basically you have two antennas to the VHF radio, the Adcock array for DFing
or the regular VHF communications antenna. The external audio jack is fed
back to the DF unit. For normal comms you use the regular antenna and for
DFing you use the Adcock DF antenna. If you are DFing a lot, get a scanner
and dedicate it the Sitek. And let VHF comms unit function unmodified.
73 Doug K7ABX

"BOEING377" wrote in message
...

Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work using
only
my existing VHF antenna and can't afford to buy something that is
marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to find.


The Sitex set works great. All you need is audio from a scanner (more
frequency selection than a marine VHF), hook up you antenna as in the
instruction manual and it will ADF just fine. This type of pseudo Doppler
ADF
works best in the open ocean where it is VERY accurate. If you are near
things
that can reflect signals (mountains, buildings etc) expect some errors.

Auto Direction Finder
 

that ADF antenna scanning buzz is annoying. One of the expensive Japanese VHF
ADFs uses two receivers that are tuned in unison. One is used for silent ADFing
and the other gives you undistorted audio. If you fish you'll never regret the
ADF purchase. Its just a matter of time before you get a bearing on someone
acting just a little bit too bored in his radio conversation who is really
nailing em. You'll see. In commercial fishing they pay for themselves quickly.
Good thing about hooking it up to a scanner is that you can nail guys on
clandestine freqs as well as legal marine channels. The MURS frequencies
around 156 MHz are worth scanning as are the freqs right above and below the
two meter ham band. Scramblers might keep you from understanding a conversation
but it wont stop your ADF from getting a bearing. The only good simple anti ADF
technology was a tone superimposed (mixed audio) on you mic line that was the
same freq as the ADF antenna commutation frequency. It worked well against the
Regency Polaris ADFs but as other mfrs used different antenna switching rates
it was not universally effective.

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One of the reasons I'm interested in having ADF capability is to find
transmitters on Marine VHF. I participate in Coast Guard Auxiliary Safety
Patrols of San Diego Bay. Besides the occasional child playing with the
radio, it's not unusual for a microphone to be stuck in the transmit
position. Having ADF would help in locating the source.
The buzzing would be annoying, but I don't expect to have the ADF in
operation at all times. I guess another option would be to have a second
radio just for the ADF and leave the volume turned low on that radio, to use
it only for ADF and not for communications.

"William G. Andersen" wrote in message
news:R_2tc.29384$wa.27813@fed1read07...
Thanks to both of you for the information. Now, how do I explain yet
another
$500 worth of boating toys to my wife (the family financier)?...

"Jerry" wrote in message
...
I think that if you check closer you will find that the 525 uses an
Eight-element Adcock DF antenna in addition to your existing VHF
antenna.
I
have one and have found it to be reliable and accurate withing the
published
specs: +/- 10 degrees. This system does introduce a buzzing sound into
your
audio that you may or may not find annoying. In an area with a lot of
radio
chatter going on, the buzz gets on my nerves and I will frequently turn
the
ADF off. Normally I keep it on.



"William G. Andersen" wrote in message
news:_iJsc.21310$wa.12601@fed1read07...
Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work using
only
my existing VHF antenna and can't afford to buy something that is
marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to
find.

Auto Direction Finder
 

"William G. Andersen" wrote in message news:R_2tc.29384$wa.27813@fed1read07...
Thanks to both of you for the information. Now, how do I explain yet another
$500 worth of boating toys to my wife (the family financier)?...

"Jerry" wrote in message
...
I think that if you check closer you will find that the 525 uses an
Eight-element Adcock DF antenna in addition to your existing VHF antenna.
I
have one and have found it to be reliable and accurate withing the
published
specs: +/- 10 degrees. This system does introduce a buzzing sound into
your
audio that you may or may not find annoying. In an area with a lot of
radio
chatter going on, the buzz gets on my nerves and I will frequently turn
the
ADF off. Normally I keep it on.



"William G. Andersen" wrote in message
news:_iJsc.21310$wa.12601@fed1read07...
Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work using
only
my existing VHF antenna and can't afford to buy something that is
marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to find.




How do you justify to your wife the $500 for the unit. Easy, do what
everyone I know does with their wives when it comes to their expensive
toys, lie about the price.

Auto Direction Finder
 

For CG Auxiliary use I highly recommend a scanner and the SiTex combo for
non-hams desiring to have a stuck mike and SAR VHF DF. On the Oregon coast
and rivers we are finding calls for help on the Family Radio Service and
GMRS frequencies. Example: the guy was in the ocean, 25 miles from where he
thought he was. He had no idea what a marine radio was, and his cell phone
was outside a coverage area. He thought the FRS radios were a great buy for
two of them for under $50 at K-Mart. Thanks to an Auxilarist who had a VHF
scanner/DF in his van, and also on his boat, he was heard begging for help
on the FRS frequencies. For serious hams, there are better units available
in kit form or blank circuit boards if you do a Google search on Direction
Finding.
Doug, K7ABX, ADSO-CM South 13 CG Auxiliary

"William G. Andersen" wrote in message
news:DTntc.307$fo5.295@fed1read07...
One of the reasons I'm interested in having ADF capability is to find
transmitters on Marine VHF. I participate in Coast Guard Auxiliary Safety
Patrols of San Diego Bay. Besides the occasional child playing with the
radio, it's not unusual for a microphone to be stuck in the transmit
position. Having ADF would help in locating the source.
The buzzing would be annoying, but I don't expect to have the ADF in
operation at all times. I guess another option would be to have a second
radio just for the ADF and leave the volume turned low on that radio, to
use
it only for ADF and not for communications.

"William G. Andersen" wrote in message
news:R_2tc.29384$wa.27813@fed1read07...
Thanks to both of you for the information. Now, how do I explain yet
another
$500 worth of boating toys to my wife (the family financier)?...

"Jerry" wrote in message
...
I think that if you check closer you will find that the 525 uses an
Eight-element Adcock DF antenna in addition to your existing VHF
antenna.
I
have one and have found it to be reliable and accurate withing the
published
specs: +/- 10 degrees. This system does introduce a buzzing sound
into
your
audio that you may or may not find annoying. In an area with a lot of
radio
chatter going on, the buzz gets on my nerves and I will frequently
turn
the
ADF off. Normally I keep it on.



"William G. Andersen" wrote in message
news:_iJsc.21310$wa.12601@fed1read07...
Anybody use a SiTex 525 VHF/ADF Adapter?
I'm considering buying one but don't understand how it can work
using
only
my existing VHF antenna and can't afford to buy something that is
marginal
at best.
I've been on boats with a Polaris (spelling?) but they're hard to
find.