"Ed Bailen" wrote in message
...
Among the stuff my neighbor left behind when moved out were two
antennas. Each looks like a dB Products 4-bay VHF array. Can anyone
tell me how I can tell from the measurements what frequency these
might be designed for? Also, is possible to change the resonant
frequency on this type of folded-dipole antenna?
Thanks,
Ed - N5KZW
Decibel Products is famous for their DB-224's, a four bay folded dipole
array for VHF hi-band (and the 2-meter ham band) and DB-420's, a 16 bay
folded dipole array for UHF (also the 440 MHz ham band).
Product catalog
http://www.rollanet.org/~rrars/db224.pdf
DB-224 Installation Instructions
http://www.repeater-builder.com/db/d...tion-sheet.pdf
READ CONVERSION OF DB-224 antennas TO HAM BANDS AT BOTTOM
Andrew Corporation has the product literature for Decibel Products (which
they purchased)
http://www.andrew.com/products/anten...a/DB224-E.aspx
http://www.andrew.com/products/anten...ollateral.ascx
You can view products on the WISCO web page
http://www.wiscointl.com/decibel/index.htm
http://www.wiscointl.com/decibel/dipoles/db224.htm
What are the measurements that you have?
Possible candidate models (dB's 4-bay products)
ASPA712 BASE ANTENNA - 4 Bay dipole VHF antenna, 150-160MHz, 6dB gain omni,
9dB directional, 500 watts. N male termination, 39lb, 22.67' long, truck
shippable, hardware supplied.
ASPB602 - 4 Bay VHF dipole antenna, 144-162MHz, 6dB gain omni, 9dB
directional, 500 watts. N male termination, truck shippable, hardware
supplied.
DB224-x 4 element broadband VHF dipole antenna.
500 watts, 6dB omni, 9dB offset gain. Harness with N male termination and
mounting hardware.
place letter below in "x" suffix above
"A" version - 150-160 MHz
"B" version - 155-165 MHz
"C" version - 164-174 MHz
"E" version - 138-150 MHz
"JJ" version - 220-222 MHz
There is also a DB224E-x series (4 element elliptical broadband VHF dipole
antenna with offset pattern)
Reviews
http://www.eham.net/reviews/detail/2083
Modify a 150-160 MHz DB-222 or DB-224 for the ham band --
http://www.w4dex.com/kc4fwc/modify.htm
w9gb