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eHam Forums => Elmers => Topic started by: N9ESI on February 01, 2013, 04:41:49 PM



Title: Grounding station in 2nd story extra room
Post by: N9ESI on February 01, 2013, 04:41:49 PM
I have a two story home and am thinking about moving my station from the ice cold basement to a cozy upstairs room. I have a common ground point on the back of my current operating desk. I have # 10 copper wire going to cold water pipe (that is also tied to ground that comes out of circuit breaker box).

How do I get a decent ground for transceiver in second story room? There are no cold water pipes near by. Should I run something out of bedroom window to ground rod or ???

Any suggestions/help would be appreciate. FYI I run a TS570D barefoot to vertical and wire antennas.

73 de Bill N9ESI


Title: RE: Grounding station in 2nd story extra room
Post by: K7KBN on February 01, 2013, 05:39:22 PM
Do you actually NEED a ground?  Does your house have the 3-prong receptacles?  If so, that third prong IS ground and for safety you don't need anything additional.


Title: RE: Grounding station in 2nd story extra room
Post by: KD4LLA on February 01, 2013, 06:44:40 PM
How do I get a decent ground for transceiver in second story room? There are no cold water pipes near by. Should I run something out of bedroom window to ground rod or ???

Do a search of this forum.  You will find to on-going war between **no ground needed** to **I have 10 eight foot cooper rods in**.

A two things to think about.  A dipole does not need a "ground".  That being said, if lightning DIRECTLY hits your house, it is toast.

I use a G5RV.  My FT-890 (ground terminal) has a wire connected to a ground rod, just outside the window of my operating position.  My power supply is grounded thru the wall outlet.

Mike


Title: RE: Grounding station in 2nd story extra room
Post by: N9ESI on February 01, 2013, 08:27:38 PM
Thanks - I appreciate the input. i do have three prong outlet.
I'm going to test the rig and see what happens. Any further comments are welcome.


Title: RE: Grounding station in 2nd story extra room
Post by: K5LXP on February 01, 2013, 08:58:07 PM
How do I get a decent ground for transceiver in second story room?

I would have to ask, "what purpose would it serve" -?

Let's see - the AC safety ground is handled by the third prong, and lightning/surge ground is done outside (you don't want it inside the house).  "RF ground" is done at the antenna unless you consider your equipment part of the antenna, but then what purpose would shunting your antenna to ground serve?

Interesting question indeed, what is that ground for...


Mark K5LXP
Albuquerque, NM


Title: RE: Grounding station in 2nd story extra room
Post by: KB3HG on February 01, 2013, 09:05:40 PM
Think about this, your outlet ground. Is it really grounded? is there s wire on the terminal,the ground terminal? You could check it with a meter.  The next question logically might be is it daisy chained through many outlets and are they properly terminated. Good solid connections. Is the wiring old and is there corrosion at any of the joints? This is only one circuit I'm taking about. Now the main panel, the circuit that originated in the shack that you power from, are the connections tight? What about the bonding ground wire to the outside ground rod (or what ever is code where you live)and the bond to the cold water line?  Lots of possible failure points. Code states minimum. a ground rod. like someone else said several is better he had 8 I think. Rods are cheap. just how much trouble is it to run a line out of the shack to grade level and run a ground outside your house? 50 Bucks? Ease your mind spend a few bucks. a direct hit will vaporize grounds forget the coax. Get on the air and have fun.

Tom Kb3hg


Title: RE: Grounding station in 2nd story extra room
Post by: WB6BYU on February 01, 2013, 09:29:08 PM
As has been said many times on these forums, there are multiple different types
or purposes for ground connections - each with its own requirements, which are
sometimes contradictory.

Mark identified the three main ones:

Quote from: K5LXP

Let's see - the AC safety ground is handled by the third prong, and lightning/surge ground is done outside (you don't want it inside the house).  "RF ground" is done at the antenna...


None of these involve running a wire from the rig to a ground rod:  in fact, that likely
is NOT a good ground on most ham bands due to resonance effects in the wire.


Yes, there are lots of old ham myths that you need a ground, primarily due to stations with
bad common mode current problems, where adding a ground - or any of a number of other
random changes to the station - may make a difference.  But it can be just as likely that
adding a ground makes common mode currents WORSE, rather than better, depending on
the coax length (and everything connected to the coax shield.)


Title: RE: Grounding station in 2nd story extra room
Post by: TANAKASAN on February 02, 2013, 07:01:08 AM
Our club radio shack is on the second floor of a building (about 25 feet up) and I'm on the third floor of an apartment block (about 35 feet) so I have some experience here:

1) For electrical supply safety an extra ground connection isn't required, make sure you have an RCD breaker on the incoming supply and an emergency stop switch is a nice thing to have.

2) If every one of your antennas are balanced (dipoles, loops etc) then, in theory, an RF ground is not required. In practice I still needed an RF ground to a convenient water pipe to reduce my RFI problems to zero.

3) If you have any unbalanced antennas such as long wires then you have two alternatives. Alternative one is to fit a counterpoise for every band you work and tune it to length. Alternative two is a ground to two or more spikes but you need to be very careful that the ground lead is not a resonant length. The ground connection should be made using the thickest braided copper you can find and some swear by ferrites at the shack end.

4) If you have lightning protection then fit this to your ground lead outside the shack. See http://www.protectiongroup.com/PolyPhaser for correct fitting details. Everyone I know just disconnects all the antenna connections when not in use.

5) Take care if you have an RF ground and an electrical ground connected together, this may be against your local electrical codes.

Tanakasan


Title: RE: Grounding station in 2nd story extra room
Post by: K4EZD on February 02, 2013, 07:03:06 AM
When I moved my rig out of the uninsulated  garage to my second floor office I had the same question and the answers on the web sites were many and diverse.  But I followed the instruction manual that came with the Icom rig (not having any other reason) as follows:  "To prevent electrical shock, TVI, BCI, and other problems, ground the transceiver using the ground terminal on the rear panel. For best results, connect the heaviest possible gauge wire or strap to a long ground rod and make the distance as short as possible. Never connect to a gas or electric pipe since the connection could cause an explosion or electric shock."   ???


Title: RE: Grounding station in 2nd story extra room
Post by: AD4U on February 02, 2013, 07:15:01 AM
"To ground or not to ground", that is the question.   ;)

Dick  AD4U


Title: RE: Grounding station in 2nd story extra room
Post by: N9ESI on February 02, 2013, 08:55:50 AM
Interesting points especially "What purpose does it serve?"

I guess I raised this grounding question because every rig has a ground terminal on the back and I have always connected this to a cold water pipe (easy to do in the basement but not in upper room). As I read through the replies (again thank you all) and contemplate the question raised above, here's the answer I come up with:

1. Electrical ground is to prevent a shock and is provided by a properly connected grounded outlet and three prong plug.
2. RF ground (in spite of what the rig manual says) is not needed for my dipole, inverted V, and Butternut vertical (vertical is grounded to copper rod).
3. Lightning protection is handled at the entry panel.

So... my plan is to plug in the rig and get on the air. Always fun to learn through a forum discussion like this. I still need to think about how I am going to get 3 antennas hooked up the the rig but that's another issue - I may try to run them up thru a cold air return or up the side of the house to one of those MFJ window feedthrough panels.

 - Bill N9ESI


Title: RE: Grounding station in 2nd story extra room
Post by: WD4ELG on February 02, 2013, 09:28:20 PM
I learned the hard way from my 2nd story window, that running a wire to a grounding rod can bring in RF currents BACK INTO THE RADIO.  Lesson learned.  I have a 3 prong plug and a 3 prong receptacle.  And I use a common-mode choke balun on my verticals to take care of THAT problem.

Now...my old TS520S is a different story.  I believe the way to address these older rigs is plug a 2 prong to 3 prong adapter into the outlet, plug the TS520S plug into that adapter, and run a short wore from the ground screw on the back of the TS520S to the ground lug on the top of the adapter.  (Not in that order.  Wire up the ground wire and insert the plug into the adapter, THEN plug the adapter into the wall outlet.  (If somebody sees something wrong with this approach, let me know.  It seems to address the electrical ground issue.)


Title: RE: Grounding station in 2nd story extra room
Post by: WB2EOD on February 03, 2013, 08:31:09 PM
This advice is based on personal experience

If you have any choice at all in the matter, put the shack downstairs.  This is especially important if your antenna is roof mounted.  The further you are from the ground the greater chance of your grounds resonating and acting as antennas.  You also don't want the equipment too close to the antenna.   


73
WB2EOD
 


Title: RE: Grounding station in 2nd story extra room
Post by: N9ESI on February 04, 2013, 07:17:10 AM
The TS520S post does raise an additional issue. I have a TS570D that has 3-prong but also my older TS530S with 2-prong cord. So the suggestion by WD4ELG is worth considering. I think before I get carried away and move everything out of the basement, I'll do some tests with each rig in the "new" location and see if any problems arise.
  -- Bill


Title: RE: Grounding station in 2nd story extra room
Post by: K8AXW on February 04, 2013, 09:20:40 AM
ESI:  Welcome to ham radio...... whose members consists of everyone from electronic engineers to shithouse lawyers. 

If every hamshack in the country was inspected by of of the ham radio electronic engineers, no doubt in my mind that 90% would be shut down for one reason or another.  I also suspect that many should be shut down anyhow because of unsafe wiring practices.  But these continue to operate and make contacts and the operators have fun.  As I understand it, the mortality rate is very low.

Then there are those like you and me that are saddled with less than ideal shack locations which prevents us from running short ground wires to multiple 8ft ground rods in nice soft loamy soil.

So, my advice is to plug the radio in, hook up your antenna and have at it!  As was pointed out in your Step 2: Use a resonant antenna like a dipole, beam G5RV, etc.  If a problem rears its ugly head, deal with it.  Chances are everything will work fine.

I DO advise you to create a lead-in system where you can at the minimum disconnect your antenna (preferably outside) at the end of your operating session.  This is simple common sense.


Title: RE: Grounding station in 2nd story extra room
Post by: WD4ELG on February 04, 2013, 04:18:08 PM
K8AXW, awesome post!   ;D


Title: RE: Grounding station in 2nd story extra room
Post by: KT4DLB on February 10, 2013, 03:05:46 PM
This brings up a question on this ground too. I'm trying to start my shack and I'm going to use a MFJ-4601 Feed line thru to run my coax and grounds from radio thru. I had plan on putting a ground rod outside of my window and run the ground to it. Someone told me that I need to run the ground to the electrical ground and that's like on the other side of the house. I do have the three prong receptables that have a ground. What should I do to be right and SAFE?


73 Lamar
KK4NZO


Title: RE: Grounding station in 2nd story extra room
Post by: W9KDX on February 13, 2013, 02:59:55 PM
After reading everything I possibly could here and elsewhere on the subject of grounding for lightning and external static, I set up a protocol where I disconnect the radio, amp etc. from any AC as well as the coax (at the entry plate)from the antennas at the end of every session.  

I have all the proper outside grounding and it is a bit more work but I sleep very well through all our summer storms.  Lightning may still impact my house, but nothing will touch my equipment.


Title: RE: Grounding station in 2nd story extra room
Post by: K8AXW on February 13, 2013, 06:15:50 PM
NZO:  I'll probably get shot out of the saddle on this post but the way I see it your have a good plan.  As for the connection to the house electrical system ground, the three pronged plugs will have to do.  

I have the same situation in my shack.  The entrance panel is on the other side of the house and it would be a major problem to run a ground strap around my house to these service ground rods.  Not only that it would look like hell to boot.

KDX has adopted a protocol, as he puts it, that is right on the money as far as I'm concerned.  

I have a stainless steel box outside and about 6ft away from the house.  All of my antenna leadins terminate in this box.  When I finish operating in the summer, I disconnect the shack leadins, pull them out of the box and hang them in a housing away from the junction box.

My major pieces have heavy strap (RG-8 shield) that connect to a copper plate on the back of the desk which in turn goes through a very heavy copper wire to a ground rod outside the house.

I also have a master knife switch (old style AC disconnect) that isolates the gear from the AC power.

That's all I can do and if lightning gets to the gear, so be it!  I feel at some point enough is enough.


Title: RE: Grounding station in 2nd story extra room
Post by: KD8TGK on February 13, 2013, 06:39:25 PM
Here's an interesting point, no-body mentioned a ground tuner. It is my personal understanding ( please be aware this my be flawed ) that if u have an excessively long ground lead it will radiate RF at various freq's. Reasoning for this: although it may be a sufficient D.C. safety ground it makes a poor R.F. ground due to length. Has anybody used the mfj-931 artificial ground, basically a LC circuit consisting of a tapped inductor and variable capacitor or home brew equivalent. The purpose of the LC circuit is to add/remove inductance/capacitance there by changing the actual "seen" impedance of the ground conductor to allow the r.f to flow to ground, ( in theory, im always confused by this point ) , which I believe helps to push any RFI to ground, and I also believe that it may be turning the ground lead into a counterpoise. I really dont know, Like I said I'm hardly an expert here and if anyone could clarify the use and or purpose of a artificial ground/ground tuner please do so. I only mentioned it because I have seen the advert's and home-brew versions, and if there was no purpose or point to making said ground tuner or if they did not work, I do not believe hams would home-brew meaningless equipment, As far as commercial companies go, they love to sell u meaningless junk, in the hopes that it breaks and you feel compelled to replace it! 73's KD8TGK


Title: RE: Grounding station in 2nd story extra room
Post by: K5LXP on February 14, 2013, 06:29:10 AM
Here's an interesting point, no-body mentioned a ground tuner.

Because it wasn't in the scope of the ground question you posted about.

Quote
if u have an excessively long ground lead it will radiate RF

What about a "ground tuner" would change that? 

Quote
the actual "seen" impedance of the ground conductor to allow the r.f to flow to ground,

Here's the kicker - just because you drive a rod into the ground doesn't mean you have an infinite "RF sink", where all energy that arrives there just goes away.  Dirt is a pretty poor conductor and RF has skin effect, making the available area for RF to dissipate even less.  So even if you created a perfectly tuned transmission line to your "ground" it would still suck as an "RF ground".

Then, we have to consider just why you have, and would want all this RF to be dissipated rather than radiated.  You're hell bent on turning everything into heat.  If you have so much "RF in the shack" you have an *antenna* problem, not a "ground" problem.

Quote
if there was no purpose or point to making said ground tuner or if they did not work, I do not believe hams would home-brew meaningless equipment,

It's a very niche application and frankly, a solution seeking an appropriate problem.  You're going to find very few instances where a "ground tuner" is effectively used.


Mark K5LXP
Albuquerque, NM


Title: RE: Grounding station in 2nd story extra room
Post by: VU2NAN on February 14, 2013, 10:04:43 AM
Hi OM Bill,

The main purpose of the main-supply-earth (third pin) is only to blow the fuse in the event of a live chassis fault.

Protection against static build-up / lightning strike is another matter altogether.
As a SWL in the mid-1970s, the antenna I used with a Philips transistor portable receiver was a long wire at a height of about 50 feet. One summer afternoon, the receiver front end blew right after a loud crackle of static was heard.

Then again, my first tube homebrew CW rig had a 3-pin mains supply plug. The antenna was a straight dipole 50 feet high. Operating on a summer afternoon, I received a jolt through my Junker CW Key and survived to hear the crash of thunder from a nearby lightning strike. I immediately yanked out the twin-line feeder and threw it on the floor (upper floor of my 2 storey house). After a few moments I was surprised to see the arc from the banana plugs to the cement floor.

Those days, in our sparsely populated area, my antenna was way above other surrounding structures. The static build-up on a 2m ¼ λ ground plane antenna would cause a whine in my 2m receiver, as it dissipated through the front end coil to ground.

Today, the conditions are totally different with my 2 storey house surrounded by high rises, cell phone towers and other structures with lightning arrestors. Problems of static build-up and lightning are a distant memory. I have not heard that static whine for years, even though I still use that ¼ λ ground plane antenna.

And I only have the mains supply earth (third pin)!

Of course, if you live in the country, the lightning arrestor at the feeder entry-point with a separate earth bonded to the mains-supply-earth is a must.

While on the subject of bonding – a friend’s shack and attached bath had a separate safety earth, not bonded to the house mains earth. His 2m antenna was mounted on a metal mast which was also separately earthed. For some reason the shack earth was open and the hot water heater also developed a ground fault. The path of the fault current was through the floating earth wire, his 2m rig, the coax feeder braid, antenna mast and finally to ground resulting in a coax cable fire.

73,

Nandu.