Finally Got My Tower And The SPT 500 Up Today.

[Marconi]

Excuse my non tech savvy...but how do you check the coax?

It's may not be the most accurate way to check and compare line loss wattage, but it's pretty easy assuming you have a good 50 ohm dummy load with an RF meter. Place the DL as close as possible to the radio and record the output (watts). Then place the DL at the antenna end of the feed line, record and compare the readings.

It's a bit more involved if your DL doesn't have an RF meter. Use your in line SWR meter at the radio/meter/DL, using very short connectors. Then check the other end doing the same, checking and recording the input and output at both points.

It's important to record these watt readings for future use, so if you ever see a noticeable difference...then you probably have some degradation in the line.

 

[Needle Bender]

It would be interesting to take your old cable and measure it's loss.

1.3db loss at 50mhz. its there version of 213. heres the pdf for it and i allways use silver pl259 connectors. i used to solder all my friends patch cords because mine would allways work right. im not that humble but still have to admit that i solder real well and the connecters on the old rg8 were done right. i still use it for my scanner antennA
http://datasheet.octopart.com/C1154.41.01-General-Cable-datasheet-127816.pdf

 

[Needle Bender]

you dont think raising the antenna higher could account for the 1/2 s-unit increase ?

i was wondering who would catch that. i checked it when it was at the old hiegth, when it was all the way up(17 feet higher) i got more then a s unit improvment

 

[Eastside]

It's may not be the most accurate way to check and compare line loss wattage, but it's pretty easy assuming you have a good 50 ohm dummy load with an RF meter. Place the DL as close as possible to the radio and record the output (watts). Then place the DL at the antenna end of the feed line, record and compare the readings.

It's a bit more involved if your DL doesn't have an RF meter. Use your in line SWR meter at the radio/meter/DL, using very short connectors. Then check the other end doing the same, checking and recording the input and output at both points.

It's important to record these watt readings for future use, so if you ever see a noticeable difference...then you probably have some degradation in the line.

Cool....thanks for the info.

 

[Marconi]

Cool....thanks for the info.

ES, if you get a chance to test your lines, post your results.

 

[Grim Reaper]

Yep...I did not like using it...but have you seen the price of the good stuff?
The mini 8 was belden...so it is prolly pretty good quality?

Belden has been making coax for over 40 yrs that I can rember and they invented the 'mini8' and unless your using a large amp. loss on the small coax is miniscule at best. if i sound uphanded please to read this that way. I only like to share what Ive learned growning up round bussiness band and CB. thank you for allowing me to join yalls forum

 

[hotrod]

glad ya like it eastside.

 

[Marconi]

spt500's are hard to beat
mines been up for 20+ years now just gets better with age !

5150, back in the day I had an old Starduster up for a long time too. I saw similar results...getting better with age I thought.

However, on taking it down I found the feed line had deteriorated due to moisture and that 100' line attenuated the heck out of my signal. On checking I put a 100 watts in, and got less than 10 watts out using a dummy load with a meter.

While I was working the setup on air, I noticed the SWR seemed to only get better and better, and bandwidth showed flat from 11 meters to 20, and that ain't right. I had buddies close by that commented that my ears were better than theirs, and I realized that too, but I could never explain, except to say it must be the old Starduster.

This antenna seemed to work very well for both TX/RX and for local and DX, so I wasn't ever alerted. I also didn't show my contacts a good signal like the other guys close by...and at some point this fact came to light. On taking this clear coat coax down I could see signs of deterioration to the shield at various points along the 100' run, and I cut it open to see. The shield was tarnished and looked of green mildew. The A99 is another similar antenna by design, but the SD'r feed point is uniquely bad a letting water go straight into the coax over time. The HSP500 may not be nearly as bad, but it looks like it might also let water in via the coax connector.

You might need to check your feed line for unusual loss if you see similar symptoms, but don't destroy the line like I did. I can't in good conscience recommend its re-use, but you may want to hook it back up...if you trust the line after such a discovery, or you find its use better than a new line like I did.

I would have never thought it possible, but it happened to me. I was really surprised at how little signal it can require to make a contact.