Antenna comparison Motorola and shakespeare

[Fv/amy renae]

Greetings, I currently have a motorola tdd6073a.
Few friends have Shakespeare 476 classic antennas. We operate on the 156-174band for commercial fishing operations. Anyone here might be familiar with these two antenna that could tell me which one should have better range? Thanks

 

[BJ radionut]

Both antennas have similar specs.
Motorola: 21 feet long...shows 5.25 DB gain(mil-spec gain) at 156. MHz frequency
Shakespeare 476 classic: 22 feet long shows 10DB gain (Mfg. Rating) at 155-159 MHz frequency.
Both have similar construction...so might be a toss up.
Good to excellent coaxial cable at those frequencies is necessary but depends on total length from radio to antenna.
Total length of cable less then 50 feet Belden 9913(RG-8 type) would be suggested.
Over 50 feet: Suggest LMR-400 equivalent type (many manufacturers)
Power output of radio will depend on distance also...Higher power equipment should equal greater range.
Hope this helps
All the Best
Gary

 

[BJ radionut]

https://shakespeare-ce.com/marine/product/476-vhf-antenna/

http://www.repeater-builder.com/antenna/pdf/mot-vhf-hi-gain-ant-specs.pdf

 

[Fv/amy renae]

Thanks for the reply BJ, yeah Im using the heavy black rg8 wire only got about 30’ run. So is it a direct comparison of 5.25db vs 10db or are they different dB ratings? The Shakespeare 476 classic is the go to antenna in the commercial work boat world. Acquired the Motorola for 20 bucks and figured it would be worth a try. Seems to get decent range haven’t figured out exactly how much yet. Wondering if the Shakespeare is worth the upgrade. Seem to be identical in appearance. Most guys are using the yaesu 2980r with Shakespeare antenna. Thanks for the insight

 

[BJ radionut]

Many things will affect range. Your ok on the coax that length. The other items are power output, placement of the antenna, highest point practical on the top of the boat for one.
The antenna in clear space. Nothing obstructing, height above water etc.
The cost factor you have on that Motorola antenna, I would go with it.
The difference in the "stated gain" could truly be very little. The "mil-spec" rating of the Motorola could be possibly closer to true gain than the Shakespeare rating.
The manufactures ratings tend to be somewhat higher, as most are not forced to adhere to "real testing" as in mill-spec ratings.
I would use the antenna "as-is", I think you will find very little if any difference between the two for now.
Good Luck
All the Best
Gary

 

[Fv/amy renae]

Thanks again Gary, good to hear the Shakespeare unit is pricey close to 1000.00 shipped. I was worried I basically had a 5db antenna vs a 10db.

 

[Jay Mojave]

Yeah these Shakespeare Marine Antennas work well. Spent 4 years on a commercial fishing boat, fishing for Albacore Tuna in the Pacific Northwest. These antennas need to be installed as high as possible to take advantage of there low angle of elevation.

Some boats will install these antennas as high as they can, and then another much smaller, way less gain antenna, installed way lower. The lower low gain antenna is for fishing near a running partner boat, while not sharing good fishing info, being heard all over the place. LPI (Low Probably of Intercept) and the operator using the low power 1 watt setting.

I am sure you have heard about Pirate HF Frequencies, fishing boats using HF Frequencies outside the Marine HF Bands. Tuning around the bands at times you can hear a fishing boat calling another fishing boat with the Diesel Engine noise in the background audio, and the informal radio talk like, "Heah Fish Head do ya pick me up" Kind of fun to listen to. Good luck on your antenna install.

Jay in the Great Mojave Desert.... "Next Gas 150 Miles"

 

[BJ radionut]

http://tesystems.com/150-174.htm

http://tesystems.com/index.htm

 

[Dr_DX]

Thanks for the reply BJ, yeah Im using the heavy black rg8 wire only got about 30’ run. So is it a direct comparison of 5.25db vs 10db or are they different dB ratings?

You can bet that if it doesn't state it, that a DB rating is in DBi. So the Shakespeare 476 classic is actually 7.85 DBd, while the Motorola is 5.25 DBd.

Always a 2.15 DB difference between DBi vs. DBd.