There are slight construction and electrical differences
between the MAB and DAV antennas.
Above.
Antenna is only partially extended.
DAV MAB antenna is a telescopic whip with a base loading coil. The whip is brass and the housing below the whip is fabricated from plastic/bakelite. The DAV case is wood. The MAB case is plastic/bakelite. Fully extended the whip is approximately 72* inches. The mast section below the loading coil is not part of the antenna and is used to store the whip when collapsed. The radios are easy to find but the antenna is rare. Good luck.
* The specifications in the manuals state 85 inches. On the antennas that I have- -I measured approximately 72 inches.
Click
to Enlarge - - I apologize for the small print.
Actual loading coil tuning information is presented at the bottom.
DAV-2
Assembly
The
short antenna lead connects to a internal loading coil. The loading coil
can be tuned.
The DAV antenna lead uses a plastic/rubber feed through.
The MAB uses metal with rubber insert.
The MAB antenna lead housing assembly is metal. The wire antenna lead is insulated via a rubber insert.
The DAV coil L301 contains less turns and less inductance than the MAB coil.
Q.
Is the frequency coverage different between the two radios?
A. No. both state in the specs as covering between 2.3 and 4.5 Mcs.
Q.
Why the big difference in inductance?
A.
The DF assembly coil L402 on the DAV effects the tuning.
Q.
Can I uses the MAB antenna on my DAV?
A.
I think you can.
Q.
Does the length of the telescopic whip different between the two sets?
A.
No the specs call for 85 inches on both.
Q.
My whip measures approximately 72 inches. I got gypped.
A.
Same here on both DAV and MAB units.
A.
I want to set up my set on 3.8 Mcs. What inductance is necessary?
A.
On the DAV it was approximately 65 uH. MAB I forgot to measure.
Q.
How do I set the proper inductance for 3.8 Mcs.
A.
First tune L301 for max receiver noise level. Then transmit and tune for
maximum Field Strength
CLICK to enlarge
Sketch from the MAB manual.
The
antenna lead uses a "snap" connector. Sewing store?
The antenna connector is similar to these clothing snaps available in many different sizes.
Often the antenna lead wire is deteriorated but can be easily replaced.
When checking for
continuity from the antenna lead to the mast via the loading coil should
be approximately 8 ohms.
The antenna must have the bottom section extended in
order to make contact with the internal wiper inside the plastic housing.
The hardwood antenna mounts are glued to the side of the DAV case.
The bottom DAV mount has a hole for the bolt on the end of the antenna.
The MAB antenna mount is the side of the canvas bag.
The antenna mount for the MAB is just a side pocket. KISS
It comes with a #2 pencil.
The DAV antenna will have a bolt at the bottom. The MAB antenna will be missing the bolt.
The DAV and MAB antenna have the same form but different
loading coils.
The telescoping antenna has a rubber tip which locks the collapsed whip into the top of the coil housing.
A external mount for the antenna can be fabricated from 3/4 inch PVC (schedule 40).
CLICK
to enlarge.
Tuning
via receiver noise and Transmit Field Strength is important other wise
you will wind up with a non resonant 70 inch antenna and piss poor radiation
and reception.
A simple FS meter can be constructed with a few components and a meter
- Use your Hand Book.
Info on Field Strength meters and the ME-61 can be found:
http://k4che.com/ME-61/ME-61.htm