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I finally ordered the new tower today.

Cool! What kind is it? It looks like a Dobsonian type perhaps. It looks like at least a 6 inch? Maybe 8 or more? I have a 4 1/5 inch reflector but the primary mirror is out of whack. It needs to be re-collimated. It got knocked over and the mirror was knocked out of whack and the secondary mirror shifted. A single point source of light like a single bright start shows up as several blurry blobs. It's been like that for several years and I just never bothered with it. I have been thinking about a nice Dobsonian type of 8 or 10 inches but have too many other things to spend my money on at the moment and for several moments to come too I think.
 
It's a Zhumell Z12 reflector with a 12 inch mirror. 1500mm focal length. I also have a Bushnell 4.5 inch reflector that is useless with its supplied mount. I hope it will be usable after it has a new mount built.

I have a laser collimator that could bring your scope back into usable alignment. Awaiting another collimator to arrive to get things even closer though.

The sky at 5am looks better, but with daylight just an hour away it's not worth the effort to drag things outside. Maybe Friday and Saturday night will work.
 
Well.......I attempted to get some ground rods on the tower today seeing that it was a beautiful sunny day in the high 60's to low 70's. It was quite windy today which was a good thing as it kept me cool and drowned out the curse words. :censored: All I got out of the endeavor was an aggravated torn leg muscle and a possible hernia. {Cry_river} Remember the layer of shale/slate in the tower hole? It's depth below grade was accurately measured as today as every ground rod that was driven only went to a depth of 24-26 inches before hitting solid resistance. Back to work tomorrow but next weekend perhaps I will get some solid galvanized steel rods, I was using 1/2 inch copper pipe today, and see if the rental shop has a ground rod adapter for their electric jack hammer that I used to finish the hole. I was able to bury the chisel point tip all the way into the soft shale so I hope that I can drive the ground rods in a couple feet to make a depth of at least 4 feet. i know the ground is wet down that deep as water was running thru the shale INTO the hole while I was digging. :cry: It looks like I will have to install at least two rods per tower leg, another at the cable entrance to the house which will be MUCH easier, and a couple along the length of the bonding cable leading into the house at whatever depth they will go. Jeesh.....the smaller old tower was so simple to ground as the shale/slate bed was much deeper over there but tree growth and proximity to the house and out-buildings was preventing me from installing anything bigger than an A3 tribander and even that had issues when raising and lowering it. The new location is free and clear for anything I may ever put up.

I wish I had a 5/8 concrete drill bit eight feet long. :sad:
 
Surely all of the building contractors that live/work in your area are both well acquainted with the problem and the cure. And the means to do the drilling for a price. Sure you aren't the first nor the last person that needs a ground rod installed.
 
Your are right however most throw a ground plate into the foundation hole before back-filling the cement wall. It's a lot easier that way. Actually ground rods are getting hard to find as most things use a heavy galvanized plate instead. Besides I just can't see paying out a contractor's wages to drive a dozen rods. There are a lot of cheaper ways to do it with the best being like i said about renting the jack hammer with the ground rod driving adapter. That way I pay $50 for the entire job instead of that much an hour.
 
Today I picked up three six foot galvanized ground rods. I wanted the ones with a heavy copper plating but had to settle for the zinc galvanized rods instead. With the use of a 10 pound sledge hammer I was able to drive a rod into the ground all the way making it about four feet into the underlying shale bed. Man, it took some effort to do it too! It was both disheartening and encouraging to see the rod sink further and further with every blow from the sledge hammer. This was because although it was indeed going in it was only going in at about 1/8 inch every time I hit it.

Well that is one in and at least two more to go and maybe as many as five more at the tower base. Another three between the house and tower and another couple where the cables enter the house.Those should all be easier however. Not easy, just easier.
 
albeit slow, progress is progress! makes me count my blessings i have no hard rock in my area...but I have a tower planned this summer and alot of tree roots.

best of luck, take it slow, not worth an injury.
 
Well I thought it was about time for a small update. The 2m and 6m yagis are still on the old tower as is some of the heliax cables. I did finally get around to some grounding work however. I was not concerned about a lack of ground over the winter months but the threat of lightning is now upon us and even though I have no cables installed and coming into the house yet the tower needed to be protected from strikes with a decent low impedance ground. I attempted to drive some 1/2 inch copper pipe into the ground as ground rods but due to the underlying shale/slate bed it was impossible to drive them over 2 feet down. I purchased three six foot galvanized ground rods and sharpened the tips on the grinder to make a nice point. Using a 10 pound sledge hammer I was able to drive one in the full six feet, that's four feet into the shale/slate which was not an easy task. Each blow yielded only a gain of 1/8 to 1/4 inch or so but it was worth it getting the rod into the wet ground. The other two rods are about four feet and four and a half feet deep with room to improve. The day I was driving them, yesterday, was the morning I came home from an overnight shift and just didn't have anything left in me to finish the job. The plan is to have three rods with each one connected to a different tower leg and all connected together. From these three rods I will install another three spaced further from the tower. The bonding cable from the tower to the house will have an additional three rods along the lengt6h and another one or two at the entrance to the house so I have lots of ground rods to install yet. The further from the tower I get the easier it will be however due to the lay of the land and the underlying slate bed.Below are a few pictures of how to connect the ground wires.



I used a short piece of 1/2 inch copper pipe flattened in a vise on one end to form a connecting lug for the ground cable. The cable I used is 000 gauge and just fits inside the 1/2 inch pipe nicely. I used Silfos and a torch with MAPP gas to braze the connector onto the cable. NEVER use regular solder as it will vaporize immediately in the event of a strike and cause the ground connection to blow open leaving you with nothing. The Silfos is a silver/copper/bronze alloy and melts at a very high temperature and using the size cable I had even the MAPP gas and high temperature burner head was barely enough. This is the end result. I drilled a 3/8 hole in the lug BTW for attaching it to the tower and slipped a piece of heat shrink tubing over trhe joint to keep water/snow etc out of it to keep it from freezing and possible breaking. It probably wouldn't anyway but it looks nicer at least.

img2366xi.jpg



Something I learned a while ago and neglected to do years ago on another installation was done this time. I learned that copper will strip zinc from steel when in direct contact in a wet environment. This explains why on my old tower there is a rust spot perfectly shaped like the copper ground lug right under it. The tower is galvanized with zinc and the copper stripped the zinc off the steel. You must use a non-reactive metal between the copper and the zinc covered steel. I used a strip of stainless steel which will not react with either the copper or the zinc. One end has a 5/8 hole for a tower bolt and the other has a 3/8 hole for the ground cable.

img2364p.jpg



The other end of the ground cable is connected to a ground clamp. I replaced the brass screws on the clamp with better stainless 1/4-20 bolts. The middle core of the ground cable is clamped using the normal ground clamp hole while the outer spiral wrap is unwound and placed under the clamp itself and clamped between the clamp and the rod as the cable itself was too large for the single hole itself.

img2362h.jpg



img2363g.jpg



The finished ground cable installation on one leg. Total length of the triple ought gauge cable is 21 inches from tower leg to ground rod. The other two leg and all other ground connections will be done the same. I may install a second clamp on the cable at the ground rod for a better connection. The discoloration of the cable is due to the heat used to install the attachment lug.

img2365m.jpg
 
very nice

thanks for all the how to...

on the stainless steel strips for the non-reactive metal between the copper and the zinc covered steel tower,

did you make these yourself or find those out at a hardware store by chance?
 
They are just a piece of scrap stainless steel I picked up at work. We deal with a lot of brass and stainless and some aluminum at work and most of the scrap is not suitable due to size or shape but once in a while the scrap bin yields something useful to me. I used stainless because aluminum is fine with zinc but not copper. Brass is fine with copper but not zinc. Stainless is fine with both.
 
Also you can use an electric jackhammer to install grounds rods....just takes about a minute or 2 to push each 1 into the ground
 

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