Glass Mount 2m/70cm Antenna

[Harlock]

I have a handheld Baofeng that I'd like to be able to hook up to an external antenna on my Subaru Crosstrek. I recently put a glass mount scanner antenna on the car, and it seems to be working well.

For the max of 8 watts that my handheld can put out, will a glass mount antenna work well? I figure it surely must be better than trying to use the radio in the car, even with an upgraded antenna (Nagoya NA-771).

Your thoughts & advise are appreciated.

 

[popnokick]

Yes, glass mount antennas work better than anything that is INSIDE the car... but for transmitting, only marginally. I am assuming you plan to transmit with a glass mount antenna? I only know of one glass mount that supports transmitting. All of the others are receive-only. The one that does support transmitting is a Larsen / Pulse Electronics. There are reviews on exam.net. Better than a glass mount would be something permanent... or even a lip / edge mount antenna. A mag mount will be better as well, but then you'll have to deal with paint scratches if you plan on using it on a regular basis.

 

[krokus]

The on glass is far from great, but works much better than an antenna inside the car.

Sent via Tapatalk

 

[Harlock]

popnokick - I did not know that the glass mounts were receive only, so I'm glad I asked. I will look into the Larsen model you mentioned. I'm not opposed to a mag mount, but I am trying to keep the install simple yet somewhat 'built-in' in appearance.

 

[k7ng]

On-Glass antennas

Please be aware that most vehicles these days use 'passivated glass', which is essentially tempered glass with metallization in the form of molecular-size particles embedded in the glass. This is apparently to reduce UV coming into the car (which degrades the plastic and other synthetic materials used in the passenger compartment) and (I have heard) reduces RFI from all the compuer hardwarew modern vehicles have.

The reason I am saying this is that the passivation severely degrades the performance of the 'on-glass' antennas. The passivation causes severe heating and can actually crack the glass if a fair amount of power is used, and certainly attrenuates the RF (both transmit and receive)... the losses caused by the passivation manifest as heating of the glass between the two pieces of the antenna. You would probably find that the VSWR is poor. One manufacturer of on-glass antennas basically says not to use them on cars any more.

 

[popnokick]

My glass mount antenna works quite well, HOWEVER it is on a 2006 Jeep and I believe it does NOT have passivated glass with metal particles. So heed the caution from k7ng and test ahead of time, or use the glass mount only on an older vehicle.

 

[Harlock]

Thanks for all the input, everyone. I checked the writing on the glass and the only words listed on the windows don't have to do with solar or UV, however I'm not going to take a chance. My glass mount scanner antenna works alright, but that may be because it is just receiving.

I ordered a mag mount, with proper adapters to fit my Baofeng SMA jack, so I'll have an SMA-F to BNC-F on the radio paired with a BNC-M to SO-239 adapter to attach to the antenna cable's PL-259 connector. This way, I will be able to quickly attached and release my radio from the cable with the BNC.

 

[SteveC0625]

 

[K3EP]

Harlock. I have been using glass mounted Larson 2m/440 antennas for decades on my Ford vehicles with no issues. And as discussed above, some glass mounts do have issues and some don't all boiling down to "is there metal in the window to tint it?" But as also mentioned above, using glass mounted antennas is a compromise. While I don't have any issues hitting repeaters 20-40+ miles away, a mag mount, or even better a permanently installed antenna on the roof is the better (and more RF efficient) solution. But I'm happy with my install.

 

[jaspence]

Harlock, there are adapters that go directly from the SMA to the PL-259. The lower the number of connections, the less chance of loss or mismatch. http://www.amazon.com/Handheld-Coaxial-connects-Station-Antennas/dp/B00B3KXNPA is the link to an example. The thinner coax makes it much easier to handle if you are not us9g a speaker mike.

 

[Harlock]

Harlock, there are adapters that go directly from the SMA to the PL-259. The lower the number of connections, the less chance of loss or mismatch. http://www.amazon.com/Handheld-Coaxial-connects-Station-Antennas/dp/B00B3KXNPA is the link to an example. The thinner coax makes it much easier to handle if you are not us9g a speaker mike.

Yeah, I was concerned about the possible loss using 2 adapters instead of just one, but I figure I'll try the BNC route since it will be a lot easier to attach and release than a cable that needs to get threaded round and round. If the signal is suffering too much, I'll switch to an SMA to PL-259 adapter only.