Towertalk
[Top] [All Lists]

Re: [TowerTalk] DIY conduit locator?

To: "[TowerTalk]" <towertalk@contesting.com>
Subject: Re: [TowerTalk] DIY conduit locator?
From: Grant Saviers <grants2@pacbell.net>
Date: Tue, 3 Nov 2020 09:10:39 -0800
List-post: <mailto:towertalk@contesting.com>
Thanks for all of the suggestions.  They catalyzed a design I built.

I bought a DIP14 1MHz crystal osc on Amazon, so I built an RF source for 3x AA battery power. It includes a 5th order Butterworth LP filter (ELSIE cad) to be nice to others.

Hooked it to a spare 110' LDF4 in a 3" PVC conduit down 18" (2 other LDF4 grounded both ends are in the same conduit). Using a Tecson PL660 receiver I could find the conduit within a couple of inches over its full length by holding the receiver vertically at shoulder height. A deep null was directly over the conduit. With the SSB BFO on, a same frequency local 50kw BCB audio was reduced to garbled.

Less than $20 for everything except Tecson (owned for RFI chasing).

Grant KZ1W

On 10/28/2020 12:19, Joe Subich, W4TV wrote:
On 2020-10-28 11:11 AM, Grant Saviers wrote:
 > Trying to find a design for a empty conduit tracer.

Plastic or metal conduit?  Empty or in use?

I've used my old "tone and trace" device to find buried wires
(irrigation controls and valves) where I had some general idea
where they were.  Something along the order of this:
<https://www.google.com/aclk?sa=l&ai=DChcSEwiPhN62_tfsAhXFnLMKHUqjCDMYABANGgJxbg&sig=AOD64_0Pp00PBuNdaGEXNM7c-CFrDS0vOQ&ctype=5&q=&ved=2ahUKEwj1qta2_tfsAhWmpFkKHSq1BxEQ9aACegQIDhB6&adurl=>

Google "Wire tracer"

The alternative, if you have plastic/empty conduit is to push
a single wire through it, ground it at the far end and feed
the wire with an Elecraft XG3 at 0 dBm on 160 meters (tune it
down to your AM radio range if you can).  I suggest 160 tuned
down to AM so you can use the "null" of the AM loopstick to
better locate the signal.

73,

    ... Joe, W4TV


On 2020-10-28 11:11 AM, Grant Saviers wrote:
Trying to find a design for a empty conduit tracer.  We've dug at a couple of places at the 501c3 where it was "supposed to go", NG. Seems to me this is a simple widget for energizing a test wire in the conduit or some sort of mouse - LF or magnetic placed on the end of a snake.

Some googling hasn't found a design so hoping a towertalkian has a design or link to one that works.  This 2" conduit was installed some time ago at 24" depth but where it routes is now lost.

The commercial tracers are $3000.  My budget is more like $20.  The usual AM radio and dongle SDR's are available.

Also interested for when I need it to exactly locate my coax conduits before digging.

Grant KZ1W
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
<Prev in Thread] Current Thread [Next in Thread>
  • Re: [TowerTalk] DIY conduit locator?, Grant Saviers <=