OPEK VU-1501

[VA3SNW]

Hello All.
My experience with an Opek vu-1501 has not been very good. I bought my VU-1501 at Dayton from a dealer in the main rooms of the convention. Being brand new and a different mount I bought an Opek adapter to go from my NMO to a PL259 mount for this new antenna. My first thoughts of this antenna using the adapter showed me a high swr. With a little experimenting the issue was that the ground plane was too far from the antenna using the adapter. The adapter is almost 2 inches up before the antenna was screwd on making it too high for a good ground plane.
I ripped the truck apart and rebuilt a new pl259 adapter that allowed the antenna to screw right down to the roof and having a good ground plane made all the difference and an swr that was basically flat.
2 months later I noticed I had a problem on 70 cm band and hooked up my meter again and found high swr on the 70cm band and a little higher than normal on the 2 metre band. Left meter in circuit and within a week both bands rose up to a high swr. I didn't think the antenna was bad so tore my new mount install all apart shotened all grounds and  replaced the coax thinking this was my problem. This didn't improve anything so began trouble shooting the antenna. I didn't have an antenna that would fit the pl 259 for a quick test so was stuck with the VU-1501 for an antenna to trouble shoot. Spent a few hours rebuilding the mount and adjusting lenghts on this antenna to no good results.
Finally built up a PL259 cable end and stuck a 20 inch piece of welding rod in the centre connector to make a simple antenna and using my power SWR metre cut the length down until it resonated in both bands as close as possible. This proved to me that the 2 month old VU-1501 antenna had gone bad.
I contacted Opek and they politely sent me a new antenna with the return of the bad one. This cost me close to $15.00 to send the old antenna and probably 5 hours of work to trouble shoot and rebuild the mount.The new antenna had a flat swr and my thoughts were that I had 1 of 1000 bad workmanship, just my luck!
1 year later after the VU-1501 was replaced the antenna crapped out again. I have been running my SWR metre in circuit since the last problem I had with this antenna so noticed right away when the swr went bad again. I noticed the SWR on 70 cm go all the way up on my metre when trying a contact up near Haileybury Ontario. by the time I made it home 9 hours on the road the swr on 2 metres had climbed up to 2 and by the end of 2 days had climbed to 3.
I contacted OPEK October 3rd about the bad VU-1501 and had no response for 6 days. Re-sent another email October 9th and a note that I wanted a response by the 14th of October and have had no response from them.
I can only conclude that OPEK does not want to respond to my complaint and that the VU-1501 is a very poor choice of an antenna. Meaningless to say I will be buying another antenna but not an OPEK.

Don

[VE3 MUN]

wow, I have an OPEK antenna on my car Don,It might be a good idea that I check it, I might have the same issue as you did. I have an Antenex antenna for UHF, the phantom series antenna , I thinks its TRA4303 Its white, you can also purchase them in black TRAB 4303, these are 430-450 MHZ with 3DB gain and I have been able to hit chathams UHF machine from windsor. Antenex and MaxRad are a good commercial make for amateur/commercial/air craft/ marine/ as well as WiFi. I used to used a Maxrad VHF quarter wave and it worked very well with flat match, but when I went to the dual bander I didn't really want 2 antennas so i found this OPEK dual bander and have been using it for a few years now, but hearing what happened to you Don I will be looking into mine. I am not sure of the model number, this is an older antenna with the PL250 connector like yours. Personally I like NMO, I have NOT tested the Antenex dual band antenna. I see good reviews on them, they are a bit pricey but seem to be rugged.

You can find these antennas from a few places:

www.ebay.ca
http://www.theantennafarm.com/catalog/

The antenna farm also has most commonly used antennas on ebay when you search Antenex or MaxRad

Adam
VE3 MUN

[VE3LFD]

I have also had bad luck with some of the offshore antennas getting water into the coils. I check them regularly. My Diamond tri-bander gets water into the coil so I take it off and set it onto the heater for about a month. (I have two now.)  I have tried silicone grease, heat shrink tubing, silicone glue,... Nothing seams to be perfect. (don't try the glue it is to hard to get off).
 I have had coils just go bad with Opek.
On my pickup I put a short simple dual bander with no base coil. But the cheap plastic MNO base cracked in the sun. I put a new North American built base on it now it works fine.

Bill