Need help identifying this type of antenna

[techpcpro]

This looks like the modern MFJ apartment antenna. It has coils that a person can put on, unfortunately I don’t know the values of the coils. I have one box that has the number "20" stamped on it but I don't know if it’s really for the 20 meter band. I included some pictures to see if anyone can help me identify what band the coils are for.

 

[Captain Kilowatt]

This looks like the modern MFJ apartment antenna. It has coils that a person can put on, unfortunately I don’t know the values of the coils. I have one box that has the number "20" stamped on it but I don't know if it’s really for the 20 meter band. I included some pictures to see if anyone can help me identify what band the coils are for.

And just where did you include these pictures? :blink: They are not here.

 

[techpcpro]

I can't post pictures

They were oversized so I corrected the size and now every time I upload the pictures it keeps timing out on me.

 

[2RT307]

Easiest way is to use a site like photobucket, upload your pic to the site, and put the link here.

73,
Brett

 

[The DB]

Well there is the MFJ-1621, the MFJ-1622, or the MFJ-1623. These are from last years catalog so I'm unaware if they added any others. Pictures are in the links...


The DB

 

[techpcpro]

These are the coils.

I would like to figure out how this type of antenna works and what coil works with what frequency.

 

[techpcpro]

MFJ-1622

Seems to be something like the MFJ-1622, unlike the MFJ-1622 it seems that you change out the coil when you want to change frequencies. I need to figure out what frequences the coils work with.

 

[vkrules]

I can't identify it. Whats the problem doesn't it work .? For fear of stating the obvious have you tried it shouldn't be to hard to work out.

 

[t77chevy]

I didn't notice in the pics if the coil is in the center or base loaded ...either way it's a simple loaded short vertical .The antenna will work and the desired band and any higher "via shorting out turns in coil" and also a 1 Henry inductor is shunted to ground "normally if center loaded" to raise the low ohms impedance to 50 ohms' if it's base loaded it may still be required if the coil itself doesn't shunt to ground "like a Texas bug catcher" just of course smaller coils. A friend with an antenna analyzer could tell you what band each coil is design for by reading zero reactance "0j".
Hope that helps
73

 

[W5LZ]

The larger number of turns in the coil the lower the frequency. The smaller number of turns the higher the frequency. Try the smaller coil on 20 meters and see what happens. Without some test equipment, how else can you find out?
- 'Doc