Topics

Help with choosing coax for loop amplifier


chipbutty
 

I'm primarily a radio listener and not a ham. So my knowledge of antennas and cables is minimal! I've received my loop amplifier from Chris. It looks like I need to buy two runs of cable, one from the 'outdoor' unit and one from the indoor unit to my radio. I'm using the loop inside so I only need a very short cable from the outdoor unit to indoor and a longer one from the indoor unit to my radio, maybe two metres.

Can anyone please advise me on the type of cable needed and where to buy. There appears to be a bewildering array of cable types. Then I read about some losing signal strength or picking up too much noise. I would also want the cables to come with connectors on each end. Looks like I need BNC. I have a BNC to 3.5mm jack adapter I can use to connect to the radio.

Finally. I'm not sure why the indoor unit comes without an enclosure. Are people leaving them bare? Should it be put into an enclosure? If so does it matter what material it's made from? Has anyone found a suitable enclosure to buy? I've had a dig around but everything is too big.

Thanks for any help. Everyday is a school day.

Rob


Tom Crosbie G6PZZ
 

Hi Rob,

I would be using a 5mm coax called UR43 it is similar to RG58 but has a very slightly lower loss. You’d need a mile of it though to notice the difference!

You can buy ready-made leads on eBay; the cheapest will come from China so will involve a bit of a wait for delivery.

What kind of radio are you using? If the aerial socket is a 3.5mm jack, do be careful of the overall weight of the adapter, connector and cable as this could possibly damage the socket over time. You will also find lots of suitable enclosures, ABS Plastic or Aluminium diecast on eBay. I’ve not ordered an amplifier yet (waiting for my PayPal account to fill back up again!) so I can’t help much more without knowing the dimensions. Being handy with a drill will help. Perhaps Chris can chip in here and send me a photo and some dimensions and I’ll try and help some more

 

If there’s a local ham radio club nearby, it might be worth calling in and making a few friends as these are the things we never throw away. You’ll find they can be exchanged or made for beer money! You might also find someone willing to show you how to solder and use a multimeter. Both very handy skills. This might not be your last aerial!

Tom G6PZZ

 

From: CrossCountryWireless@groups.io <CrossCountryWireless@groups.io> On Behalf Of chipbutty via Groups.Io
Sent: 06 December 2019 19:05
To: CrossCountryWireless@groups.io
Subject: [CrossCountryWireless] Help with choosing coax for loop amplifier

 

I'm primarily a radio listener and not a ham. So my knowledge of antennas and cables is minimal! I've received my loop amplifier from Chris. It looks like I need to buy two runs of cable, one from the 'outdoor' unit and one from the indoor unit to my radio. I'm using the loop inside so I only need a very short cable from the outdoor unit to indoor and a longer one from the indoor unit to my radio, maybe two metres.

Can anyone please advise me on the type of cable needed and where to buy. There appears to be a bewildering array of cable types. Then I read about some losing signal strength or picking up too much noise. I would also want the cables to come with connectors on each end. Looks like I need BNC. I have a BNC to 3.5mm jack adapter I can use to connect to the radio.

Finally. I'm not sure why the indoor unit comes without an enclosure. Are people leaving them bare? Should it be put into an enclosure? If so does it matter what material it's made from? Has anyone found a suitable enclosure to buy? I've had a dig around but everything is too big.

Thanks for any help. Everyday is a school day.

Rob


chipbutty
 

Thanks Tom. Very useful. I can solder fine and I'm generally handy with most things. That is when I know what I'm talking about! I'm just very green around these things. Mainly because I don't really have that much interest in the Ham side of things (please don't hate me). I just love scanning LW/MW/SW listening for anything interesting or weird. 

I use a cable on the radio with a female end for the 3.5mm Jack. Provides strain relief. It's a good point though as I imagine many jack's have been damaged this way.

I'll take a look on eBay for the cables you mention and some enclosures.

I'm not sure how I'm going to explain the arrival of a child's hula hoop next week.


Tom Crosbie G6PZZ
 

I made an assumption, sorry Rob

 

You can buy connectors and coax from W H Westlake in Devon.

You’ll need to download latest price lists.

I don’t have the URL to hand but google will find him. Might have ready made leads.

 

From: CrossCountryWireless@groups.io <CrossCountryWireless@groups.io> On Behalf Of chipbutty via Groups.Io
Sent: 06 December 2019 20:27
To: CrossCountryWireless@groups.io
Subject: Re: [CrossCountryWireless] Help with choosing coax for loop amplifier

 

Thanks Tom. Very useful. I can solder fine and I'm generally handy with most things. That is when I know what I'm talking about! I'm just very green around these things. Mainly because I don't really have that much interest in the Ham side of things (please don't hate me). I just love scanning LW/MW/SW listening for anything interesting or weird. 

I use a cable on the radio with a female end for the 3.5mm Jack. Provides strain relief. It's a good point though as I imagine many jack's have been damaged this way.

I'll take a look on eBay for the cables you mention and some enclosures.

I'm not sure how I'm going to explain the arrival of a child's hula hoop next week.


chipbutty
 

No need to apologise Tom. I'm grateful for your help. I'll certainly take a look at W H Westlake. Thanks again.