The chicken stick, or how not to get killed in 1 second flat!
Working on my TUBE RIG ! 
(Rig is slang for my HAM RADIO gear or equipment) The most dangerous is the PA at 3000vdc,


The golden age of Vacuum tubes. (The topic is working on any PA, RF Power Amp.)
All voltages here, are lethal. (no second chances!)  3000 volts DC, means zero 2nd chances.  (even my weaker Exciter rig  run 700vdc SB401)
Never connect 600vdc rated meters or scopes to the 3KV high voltage nodes ever.(only use high voltage rated meters up to 10kv is wise) That includes test leads with lame 600v ratings.(avoided)
Rule one , keep hands out of the rig  turned on.
Rule two, wear no jewelery working any HV gear,  that means that Mr. Tee gold necklass , wedding band and wrist watches.
Never ever trust bleeder resistors with your life. (regardless of location of them)
Working with RF PA, mine is 2000wt (2KW) PEP and the antenna jack has 400volts that not only a shock hazard,  but a RF burn hazard. (same hazard on TUBE and that MOSFET PA output)!
With SS RF PA (solid state RF power amp ) the voltages are 48vdc inside, but not the antenna ! Do not touch any PA antenna keyed up.
Do try to be the  bird  ! The crazy bird is not grounded and is safe (kinda). '
If he man above tries to next touch the bird, both die. (this is the key fact to learn here)
If the bird or silly squirrel walks the wire and his tail hits the power pole metal or wood (telephone pole) the bird sadly explodes. ( some power lines even have squirrel guards)

The HV Chicken stick (English, the High voltage safety discharge probe) (or a Savvy stick? or a brave stick, you can't be brave if not still alive nor can you be a chicken)
Verb? did you Chicken stick it yet?  (This magic device avoids all that death inconvenience thing)
More rules for sure:
Rule 1, Do not work on your rig, drugged, drunk,  tired or distracted (turn off TV and CELL), take a nap or hire an  HV ELMER.?
Rule 2, Assume all parts inside are at 3000vdc.  (assume there are shorted parts inside putting 3000vdc where it does not belong, even the case! Which makes rule 3 next.
Rule 3, Keep the case grounded to the ham shack ground buss bar at all times. We unplugged the AC power cord and then we connect up a case main ground next, mine has rear ground stud that is grounded to my service entrance ground. (all shop benches for HV work has a ground)
Rule 4, Have a schematic of your rig, in hand , read it and know where the danger zones are, sure in the PA cages.  (Ignorance here, is not bliss)
Rule 5, You did everything right, and just before you put your fingers on the Plate caps or other HV points, you pull the line cord from the wall (why trust live to the power switch?) then using screw driver held against the case you ground the point you are about to touch, next..... (hope I saved your life.)
Trust nothing and live, trust only your actions here, use safe grounding techniques,  learn them and practice them.

First off , just let the RF AMP sit for hours, and it will be most times be safe, if not , repair the bleeder first , that means find all High voltage bleeders in the RIG  and make sure all are good. (dead cold , RIG, no voltages present using and ohm meter and your schematic)
The PA HV meter may lie to you,  do you trust your life to that cheap meter?  (I do not ever) if you do see the meter drop slowly in 1 to 2 minutes,  the bleeders may be good.  (learn that moving coil meters love to stick (watch the movie GRAVITY)
Never work inside the PA with out using the chicken stick 3 times on all known HV nodes;. (a node is a wired junction you are about to touch with  fingers)

Case in point, Heathkit SB200;. 2800KV
Next? if the HV bleeder inside the RIGS,  HV cage,  15meg ohms inside ,is still there ?AS IT MUST BE !, and working, the voltage drops below 100vdc in 1 to 2 minutes at power off (seen on the panel meter )
Yes watch it do its job using the PANEL meter set to HV , on the SELECTOR KNOB.
If the HV meter is no good or dead or sticks , fix that next. (it's a big time safety device, as is that bleeder resistor inside the RIG)

Do not use  any RF AMP (PA power amplifier) lacking a working HV meter on the panel and tested and you know it works for sure. (reliable 100%)
This  PA  by the way, loves to blow up the meter from GASSY tubes. (so putting faith in 50 year old meters, is risky !)(use the double diodes upgrade fix, using back to back 1n4001 diodes,  affixed on the rear of all meters) Or the single diode fix in my Kenwood PA.

The resistor in the Chicken stick must match the RIG you are using it ,  in our case 3000vdc. 
Some PA rigs use internal 500k home bleeders,  some use 1Gig or more. and 1 minute delays to 100 vdc discharge point. or 2 minutes for the later bleeder inside.
To my way of thinking is use a stick that will drop the 3000 volt to well below 100v, in  10seconds not minutes (less time is better for sure in human terms) I use 3k (3000) ohm resistor from all my Radios.


Do not fail to test your sticks wiring connections are good and that the resistor inside it is fully good and ready for the job.

Many old hams just jam a screwdriver in (after 5 minutes off or better 1 hour) and hope it don't spark.  (this why has merits,  in that it can't fail, metal shift of driver to case metal ground) <<< in fact I do this after the Chicken-stick does its job.

How to make a Chicken stick is not hard: DIY !


The PA RADIO AMP. uses  600vdc caps wired in series and the actual capacitor maker makers rule for max discharge rates are:
(the answer from a top CAP maker in Japan, Nichicon (LGN series) states never "exceed ripple current" spec. and that is 1.2amp on my PA, (lets call that 1amp)
Time constants matter TC.
So R  = E/I is what,  3000 / 1amp is 3000 ohms.
The discharge time is called TC, time constant, and is simple math equation
(the TC= R x C   or 3000 x 20uF or  0.06" sec.  4TC = 0.24 seconds (1/4  of a second, to hit near zero volts. 98.2% discharged = 4TC (54 volts now)
I use 3k ohm at 5 watts, resistor in line. I use only Ceramic HV rated  resistors. (best insulation on them)
The best Resistors is the lowest ohms that does not cause excessive stress on the FILTER CAP.'S.
After soldering the resistors to the wires we use  super good  insulation around the whole thing , I use a microwave oven fuse holder seen here.


USE  crocodile clips only.
 The the clamp can be home made bent metal forming a U shape and drilled tabs for #8 screw and nut. Clamping wire to screwdriver shaft. Soldering a chrome plated screw driver blade is impossible.

The simple model can wreck good capacitors, even new ones,
The clip must go the the PA chassis or Radio case ground.
The wiring must be HV rated wire, on the HV upper side, the lower side clip side can be any wire you want. (rugged)
If you hide the resistor in the PVC handle you need no HV wire nor  the fuse holder above.
All parts Sold at mouser.com  (wire at ebay as they sell short lengths)
The long handles are wise and HV wires even more so and the resistor hot end must be very well insulated.
One more example or two.
The end below is a standard banana plug male. (has solder tab on rear)
We could use 1/2"  PVC pipe,  and a a matching cap all  schedule 40, and make the handle your self. (18 inches long would work)
I use double layers of shrink wrap tubing for insulating junctures.


A 1/2" PVC pipe with end of pipe cap and a probe put on the end and the wire and resistor and the correct clip seen above.
If your hards are huge, get 3/4" PVC pipe at Home Depot or Lowes...
If real  cagey, (pun yes), (being hesitant as you think and build) you could hide the resistor in the 1/2 pipe PVC  handle. (if you ponder that a moment)  
My USA Military tool was Teflon end to end, which is 1500 v/mil.  PVC is 10kV/mm at 2.77mm that is  or 27,000 volts (27kV) Clean PVC not used, ever.
I also have this nice probe.  I bought this in their Heathkit store, in 1970s.
You can touch the probe to a node and see that it is safe and even watch it discharge live on this meter. 40KV rated too!



BOM (bill of materials) DIY:
1x   banana clip male, probe tip. 6mm thread. $1 (throw away plastic part (unscrewed)
1x  3k ohm 5watt resistor ceramic. (mouser)
1x  PVC 1/2 pipe 20" long or 3 foot sections sold and cut , schedule 40. (home depot)
1x matching pipe cap to above.
1x ground wire of any stranded wire, say #18 AWG or #16 (home depot){big box stores, where wire is sold , stranded}
1x Crocodile clip. (mouser)


Old Haunts:
On my Military gear,a huge 1 million watt peak, radar ,etc.(Air Search) (Deadly Power supplies 25kv and deadly RF fields )
The gears cabinet knobs that unlock Doors or hatches , the HV , 25kv supplies, had rocker levers inside that grounded all caps at once automatically,  (not once did I ever trust those!) 
We had this Huge CHICKEN STICK made of 25mm diameter solid Teflon handle 20" long. and 6mm SST steel rod off end, hooked shape, and long wire grounding cable and clip.  We had to handle it in steep ship rolls at 30 degree's... no fun that.
Our MIL spec. chicken stick had no resistors at all, (your life wins over any potential cap damage) 


rev 3   ++++ 3-12-2016  ( less )