Andrews cable prep tool

[Bill_G]

Any problems with Andrews cable prep tools?

We spent a good part of yesterday chasing open connectors on both ends of new 7/8ths line. It looks like the problem was caused by the prep tool flaring the center conductor so the tip inside the posi-stop connector had little or no contact. I had to very carefully spread the the contacts with a small screwdriver to get a solid connection. Drove us nuts with high vswr alarms and pa fail until we got both ends perfect.

I'm an old school guy and put my connectors on by hand. But, our tower crew use the OEM cable prep tool that fits into a cordless drill chuck, and gets the job done in seconds. I've never observed a problem before. But, maybe they can be mis-handled, or maybe they wear out. I dunno, but it was a PITA to find and resolve.

[fineshot1]

The only two problems i have seen with using these tools has been either worn blades
or too much debris stuck in the bottom of them before usage. Being these fellas are in a
tower crew i must "assume" they know how to use them so i would think they clean them
out after each usage but the blades being worn out is not immediately apparent and can
cause exactly what you just described.

[Astro Spectra]

I use a plumber's tube cutter, hand tools, and a brass bristle brush to clean up. Never had a problem but I've often admired the vendor prep kits. Problem is you need at least two (1/2 and 7/8”) not to mention if you need extra tooling to work with both Andrew Heliax and RFS Cellflex.

Whatever the tool chain, the basics of the RF functions and mechanical integrity of the cable to connector interface need to be got right. On some jobs I've had to fix the rigger guys must have been in such a rush to finish the install that despite using vendor's tool the connector fit was bad. In a couple of cases I've found connectors that can be turned on the end of cables by hand.

The contract with the rigging company needs generous penalty clauses to cover this sort of thing because sometimes the problems take a while to show up and cost heaps of time to track down.

[FMROB]

Bill,

I have an extensive collection of drill operated cable prep tools, and would never look back to doing it by hand.

A few points to consider while using automated cable prep tool

1) Cable cut at blunt and should be clean and straight to begin with
2) Cable should be straight when insterted into the bit.
3) Medium speed and light to heaviy pressure needs to be placed when driving down on the cable.
4) When the tool makes the final plunge, and chamfers the center pin you will feel a click almost, stop.
5) Do not rotate bit/drill when pulling the cable out of the bit, it will shave the shield if cocked.
6) Always inspect, clean by hand the cable. If it isnt perfect re insert the cable into the bit and work it a bit.

Worth the investment, I have them in all sizes for andrews cable.

- Rob

[Bill_G]

Thanks guys. They are great tools, and the tower crew are very competent and capable. But, I'm glad to hear that others have experienced similar problems with these prep tools, and a solution. It is possible that the LDF5-50 center was a few thousandths too wide. I have had brand new bad line before. The Anritsu is a darn handy machine for finding these sorts of problems. It's disappointing and time consuming, but these things do happen.

[RFguy]

Are you SURE that it's LDF5?

We just hade the exact same issue. Open connectors.

We ordered LDF5, but it was subed out with the "new" cable, AVA5. LDF5 is obsolete.
http://awapps.commscope.com/catalog/and ... px?id=1310

The inside diameter of the center conductor is larger and we were using some connectors for LDF5. Turns out that the fingers on the center pin just fit inside the new style cable with a few thou. clearance. Result: open connector.

We ordered in the new connectors for the new cable and problem resolved.

I would go back and recheck the part number on that cable and make sure you have the proper connectors.

[Bill_G]

doh!

Where is the dope slap smiley?

Ya know, I dunno. It is worth pursuing. Thanks!

[escomm]

LDF5 may be "obsolete" but they're still manufacturing it, or at least someone has tens of thousands of feet of it in a warehouse somewhere. Can definitely be had through Talley.

[RFguy]

The part numbers for the N male and female connectors for the newer AVA5 cable is as follows:

AL5NF-PSA Type N Female Positive Stop™ for 7/8 in AL550 and AVA550 cable

AL5NM-PSA Type N Male Positive Stop™ for 7/8 in AL550 and AVA550 cable

[Bill_G]

While finishing up at each site, I inspected the cables and connectors. All of it is marked LDF5-50A, and the connector boxes, still in the trash, are correct. Since I saw not workmanship issues in the cable prep or connector assembly, I have to assume materials defects. Either the center conductor of the cable is too large, or the center tip in the connectors are too small.

[KG6EAQ]

While finishing up at each site, I inspected the cables and connectors. All of it is marked LDF5-50A, and the connector boxes, still in the trash, are correct. Since I saw not workmanship issues in the cable prep or connector assembly, I have to assume materials defects. Either the center conductor of the cable is too large, or the center tip in the connectors are too small.

I'm experiencing the same problem right now Bill. What vintage is your LDF5-50A? We tried a number of positive stop connectors and none of them fit snugly, all seemed loose on the center conductor.

[Bill_G]

As far as I know, it is new stock ordered for this project. The construction group ordered from Talley who apparently still have some on hand. I had to very carefully spread the fingers inside the connector to achieve a solid contact that survived the push and pull test. Prior to that, the slightest lateral push on the cable would cause it to go open. I could not see our climber disconnecting the stinger to the antenna on the Anritsu until he released the main line from the hanger. For a while, we were faked out thinking the stinger was bad. After he took the 7/8ths out of the hanger, a finger touch near the top connector would bounce it open meaning we had just a whisker of contact internally. At the bottom, I could not see any rifling inside the center conductor by the connector contact. Even the tiny raised portion of the continuous weld was undisturbed.

[KG6EAQ]

Gotcha, the cable we were working with has been installed for about four years and the connectors are probably two years old but new. We couldn't get a connector to sit right to save our life. When the climber tried spreading the fingers of the connector, the sweep was terrible. He was able to salvage it to a barely acceptable sweep of -15 (return loss) eventually, but nothing great. Being that it's an easily replaceable line, our current plan is to just replace it with AVA5 and new connectors, if it wasn't on a monopole we might futz with it more but the lift is expensive. Glad to see though that we weren't crazy out there last week.

[Bill_G]

We went back over all our part orders and received shipment paper. We ordered LDF and received LDF (cables and connectors). I went through the trash at the site, found the connector boxes, and verified they are LDF. Inspected the cable - it is marked LDF. As far as I can tell, this is a cable production issue. On the bright side, my fix is holding.