Hi all,
Looking at rebuilding my rig after a flooded ant.
Is it worth paying the extra for LMR400 etc rather than RG6, over say 12-18ft run?
Ta 
Greetings,
Perfect timing for your post…
I just switched today from RG6 to LMR-400 and noticed probably a 20% improvement.
Part of that could just be getting rid of two adapters that were in line.
if you have the cash, LMR-400 will not hurt.
Bob
Bob,
How long is you run?
RG6 75ohm around 6.2db loss per 100ft at 1Ghz
en.wikipedia.org/wiki/RG-6
LMR-400 50ohm around 4db loss per 100ft at 1Ghz
timesmicrowave.com/document … MR-400.pdf
It could have been removing an impedance mis-match so that there was only one (75ohm dongle to 50 ohm cable/antenna/amp/filter).
I have LMR-400 ready to go when I can finally put my setup(RPI2) in the attic and antenna on the chimney.
(currently one has $5 antennas on the basement window bars and the other has the FA antennas(both types) in my bedroom).
The 978Mhz FA antenna and a DPD 1090Mhz antenna will go on the chimney(eventually),
Jon
(1) If the cable run is 50 ft/15 meters, there will be only 1.1 dB less attenuation by changing RG6 to LMR400.
(2) The mismatch loss for each transition from 50 Ohm to 75 ohm and vice versa, will be very minimal at around 0.177 dB.
These losses added together may decrease the performance, but if an amplifier is used, it covers for the loss.
I have LMR-400 ready to go when I can finally put my setup(RPI2) in the attic and antenna on the chimney.
(currently one has $5 antennas on the basement window bars and the other has the FA antennas(both types) in my bedroom).
The 978Mhz FA antenna and a DPD 1090Mhz antenna will go on the chimney(eventually),
Jon
Few days ago, I received $5 antenna, but it proved hopeless, much inferior to mag-mount of dvb-t trimmed to 52 mm
looks like the same $5 antenna I have on my basement window bars.
At 3ft AGL, I still get 100NM in the right direction.
Hoping to get attic stuff done today(Weather is warm and I have a long enough ladder).
J
(1) Place $5 antenna on a metal sheet or can, and try it.
(2) Chop-off the dvb-t’s stock antenna to 52 mm (removable part length), place it on a metal sheet or can, and try it.
I am sure the choped-off stock antenna will give much better performance than $5 antenna.
Hi Jon,
It is a 40’of run into the s LMR-400 to the shack from the antenna.
I’m also running a Nevis filter/preamp.
This new setup bumped me up from 100 aircraft seem at the 250 mile section to over 1000 average.
if I figure out on how to post pics, I’ll post one of the antenna setup.
Bob
Very nice Bob.
My move to the attic was delayed today. I have an essay due Wednesday so had to knock out most of it today. The weather will be cooler but dry tomorrow so I hope to do a little work then.
Jon
K2TCW/VK2TCW
You gotta take care of the important stuff first.
73,
Bob
K1PCG
Conduit from basement to attic run.
I wanted to run the cable but can’t. I need to put in more conduit in the attic but found out the RJ45 won’t fit through it.
I have already cut off one end of a STP cat5e outdoor cable. I want to keep the attic end clean and intact.
I ordered the conduit brackets today. I can finish it off on Friday.
At least I don’t need to use the ladder for a while and can do the work when it is raining or during other bad weather.
Do you have the equipment to punch down your own RJ45 connectors?
I do my own.
It makes life easy.
I work in the maintenance department of a municipality and when I’m not sleeping on the job, i run cat 5e and cat6 cables.
I’ve even made custom cables for my Signalink USB modem with these tools.
Bob
K1PCG
Yes, I have crimped for rj45s and coax.
I have a simple cable tester for rj45s. Just LEDs, nothing special.
I did something similar when I ran cat5 to the fios ont. I used an outdoor shielded cable, cut off one end and fed it through the hole they drilled to power the outside unit. It works very well.
Ha! I remember those days, did that when I had Fios. That actiontec router is a piece of trash, I hear they’re still using it.
Did you still have to put in a MoCA adapter for the STB’s or did they figure that out yet?
(sorry, off topic)
I have my own router. Cisco 891 with a juniper srx210 in the wings, waiting for me to implement it.
I used the actiontec to bridge moca and provide wifi.
I haven’t wired the house for cat5/6 yet. Moca bridges work well enough. Moca 2.0 is faster.
I don’t use Verizon stb. I have a TiVo with TiVo minis.
The Actiontec router is still a POS, they are still using it.
I am using it only to bridge for MOCA for my cable boxes/tv guide/onscreen caller ID but I am using a SOPHOS UTM VM for my main router and double NATing the Actiontec to make it think it’s the external router.
Pain in the butt, but it works (and I am a network engineer by day, so it’s up my alley to make it work).
The actiontec should are not that bad. They can do well over 100Mb/s and the older NAT issues are no longer a problem.
I started out in Networks but now do firewalls and proxies.
I have two VPNs for a family VOIP system which I why I have got around to migrating from Cisco to Juniper.