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Re: NOS cermic-metal tube burn in
Hsu
开云体育Screen PS V=350V,
?anode PS V=2kV.
?? they are ?in Collins
KWS-1.
???? My friend have been burn in
for 2 hours, the bias crrrent has ben increase to 100ma, and can get more
(400-500ma) current, I think the tubes?are
good.
??????
Hsu?
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Re: Pseudo Grid Current
pentalab
--- In ham_amplifiers@..., jmltinc@... wrote:
repairing in my spare time. Amongst the defects it had, was a plate choke flash-over. This took out the .5 ohm (20 watt?) resistor and diode (on the powersupply) that hold the B- to near ground potential. It also took out a small(.1?) cap at the plate current meter (in the desk console). The schematic is notcorrect for this unit and Henry was no help. I did what I think is correct.#### Whoa. I'll be damned if I can find my henry 3k/8k ultra manual. IF u had a flash over between plate choke and chassis.... it would short out the undersized safety diode between chassis and B- When that happens, the neg of the grid shunt is now directly in parallel [via the chassis, and then the shorted safety diode] with the neg of the plate meter. The pos of the plate meter is normally directly tied to the pos of the grid meter. You now have a condition, whereby both meter's are in parallel..... so the grid meter will now read plate current! ### Now u know why I always install a HV fuse in the B+ lead ! You may well have damaged some diodes in the FWB diode assy too... [waiting for the slo breaker in the 240 v line to open up]. ### Henry, in their infinite wisdom, installed the glitch R in the B- lead.... not a smart move... since that will allow the fil xfmr to spike to full anode v, etc. ### IF u want to fix this right.... I'd install a 50 ohm-50w wire wound in the B+ lead. [or at least a 25 ohm-25 watt, wirre wound] I'd also install a HV fuse just PRIOR to the glitch. reason is... if glitch R ever exploded.. and pieces of it hung down and touched chassis.... you want the HV fuse to be on the inboard side of the glitch R.... so it will blow open.. shutting every thing down. ### I'd also install some RVS connected diodes, either 6A10 [1 kv -6A]... or PARALLELED 1N5408's [1 kv- 3A] between chassis, and B- and also some more RVS connected diodes across BOTH meter's movements. Myself, I use 3 x paralleled 6A10's in each direction..... 6 in total.... 1200A surge.[between chassis and B-].... and just 2 paralleled diodes, in each direction, RVS connected... across EACH meter. The surge rating on the diodes should be plenty high enough so they never get stressed... and never short out.... and never have to be replaced. .... then u wouldn't be having this problem in the 1st place. [Ameritron does the same thing with their one and only underated safety diode between chassis and B-..... "check to see if diode XXX is shorted"... IMO, they shoulda just sized the safety diodes right the 1st time... since they are dirt cheap] ### The kicker here is....IF u blow any HV fuse.... ur grid current is gonna go sky high..... so now u need a simple FAST grid fuse, 3agc type..... wired between chassis.. and grid shunt. [both the 3k + 8k have NO grid overcurrent protection at all] ### If u want.... install a 3agc- CATHODE fuse in the CT of the fil xfmr... either just b4, or just after the bias diodes [used for setting ZSAC] . Install a 100 k, or better yet.. a pair of 100 k MOF 2-3 watt resistors across the cathode 3agc fuse holder. Any Cathode fast fuse has to handle the SUM of normal anode current PLUS grid current. ### when config like this..... if u remove [or blow open] either the grid fuse... OR the cathode fuse... INPUT swr will rise to infinity..... shutting down ur xcvr. ### You may well have to get in their.. and draw out the existing circuit by hand.... then compare it to a standard config. I'll look for my 3 k ultra manual later on... had it in a binder. ### also... in the combo 3k/8k manual [pretty sure the 3k ultra is the same setup], Henry used a 2x piece plate choke setup.... I have the RFC's from the 8 k ultra. The big one is 24 ga magnet wire , wound on a 1" diam solid teflon rod... and measures 180 uh. The small one is just 20 uh, wound with 18 ga wire. The large choke was shorted out on the high bands,14-30 mhz...with a HV solenoid relay. ### You are gonna have to find the reason for the flash over... it might be the large choke shorting relay.... it might also be the paralleled bypass caps at the base of the large plate choke, which on the 8k are 2-3 x 4700 pf caps + 2-3 500 pf doorknobs. ## The amp works as is.. with 1500w out. So this is just a metering problem.. cuzed by a shorted diode.... caused by a HV arc to chassis...... which if the amp was config correctly.... should have just taken out the HV fuse... then the grid fuse a split 2nd later. Later.... Jim VE7RF not "grid current", but plate current. See the table below for results:Out follows the plate current. Hmmm...grid meter, here is a .5 ohm resistor shunt from ground to cathode with a 470ohm, 3 Watt series dropping resistor from the cathode side of the shunt to thegrid meter. (The other side of the meter is grounded).from the glitch R to the cathode. The meter is connected across this with a150 ohm series dropping resistor between it and the shunt R / glitch R connection. |
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Re: Pseudo Grid Current
On Nov 14, 2006, at 6:04 PM, jmltinc@... wrote:
OK, I need professional help.John = The first thing I would do is to connect two back to back 3A diodes across each meter movement to protect them from possible damage. The second thing would be to check the calibration of all metered functions against a calibrated DMM, and do whatever it takes to make them read accurately. Third, I would add a suitable glitch-R in the HV+ lead. R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org |
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Pseudo Grid Current
OK, I need professional help.
I got a basket-case Henry 3K Ultra some time ago and have been repairing in my spare time. Amongst the defects it had, was a plate choke flash-over. This took out the .5 ohm (20 watt?) resistor and diode (on the power supply) that hold the B- to near ground potential. It also took out a small (.1?) cap at the plate current meter (in the desk console). The schematic is not correct for this unit and Henry was no help. I did what I think is correct. Now my problem: The grid meter show excessive current. I am convinced this is not "grid current", but plate current. See the table below for results: Grid Current Plate Current Power Out Amp on, not keyed: 75ma 0ma 0W Amp keyed, no drive 225ma 150ma 0W Amp keyed, 50W drive >1,000ma 875ma 1,500W Notice grid current w/ no excitation and how the grid current follows the plate current. Hmmm... If I draw out how the metering is wired it looks right. For the grid meter, here is a .5 ohm resistor shunt from ground to cathode with a 470 ohm, 3 Watt series dropping resistor from the cathode side of the shunt to the grid meter. (The other side of the meter is grounded). For the plate meter, there are two series .1 ohm shunt resistors from the glitch R to the cathode. The meter is connected across this with a 150 ohm series dropping resistor between it and the shunt R / glitch R connection. Any ideas? Thanks -John |
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Re: [Amps] Variable capacitors and 4CX250B FS
Hsu
Sorry, make incorrect, WxHxD not include shaft's length.
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----- Original Message -----
From: "Hsu" <Jbenson@...> To: <ham_amplifiers@...> Cc: <amps@...> Sent: Tuesday, November 14, 2006 4:04 PM Subject: [Amps] Variable capacitors and 4CX250B FS
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Variable capacitors and 4CX250B FS
Hsu
I have 20 NOS Variable capacitors, one is 1400PF/1kV(0.65mm spacing ), another one is 200PF/3kV(2mm spacing ).
a set of capacitors(1400P/1kV+200P/3.5kV)=$80, include shipping.WxHxD=92mmx87mmx85mm( include shaft's length),weight=550g , a pair NOS EIMAC 4CX250B in papaer box=$150 I pay the shipping cost. 73! Hsu |
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Re: Inrush filament current protection
Phil Clements
I looked. In our breaker box, all the ground wires and all the No electrical difference here; but if the breaker box is to be used as a sub-panel, you need seperate bus bars for the neutrals and grounds with a removable shorting strap between the two. Only in the main service entrance panel do the neutrals and grounds all strap together. I guess a few bucks are saved by leaving out the strap and insulation for the two bus bars if one has no intention of ever changing a main panel over to a sub-panel. (((73))) Phil Clements, K5PC |
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Re: Inrush filament current protection
FRANCIS CARCIA
I get along with my guy very well for the reasons you stated. Life is short and best to get the inspector out of it ASAP.
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"Robert B. Bonner" wrote:
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Re: Inrush filament current protection
Robert B. Bonner
Yeah some of these guys interpret the code differently… Have their own
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opinions. That’s why there are lawyers and judges, hahahaha My local inspector considered the water pipe as the real ground… The ground rods as a supplementary ground. While this is incorrect it is supposed to be the other way around by definition. The water pipes in his argument are better grounded than the ground rod… The correct answers when dealing with ANY INSPECTOR are YES SIR and OK that’s good to know, hahahaha. BOB DD ________________________________________ From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of FRANCIS CARCIA Sent: Monday, November 13, 2006 12:01 PM To: ham_amplifiers@... Subject: RE: [ham_amplifiers] Re: Inrush filament current protection My building inspector did not want the ground wire in the meter socket. I ran conduit off the breaker panel to the rods. I also ran #4 over to the water main both sides of the meter. Then I showed him?the 4 #8s coming through the wall that go around the footing and through the yard. He smiled and said connect them also. Next I got some interesting lightning stories. gfz "Robert B. Bonner" <rbonner@...> wrote: -----Original Message-----
From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of R L Measures Sent: Monday, November 13, 2006 9:41 AM To: ham_amplifiers@... Subject: Re: [ham_amplifiers] Re: Inrush filament current protection On Nov 13, 2006, at 4:48 AM, Robert B. Bonner wrote: Jim,Is not 240v standard in the United States? *** You can call it whatever you want, there is no actual voltage 220-230-234-240.. So you will sometimes see it referenced 220/240 which is the correct term. Or my favorite inside electrician's joke "220-221 whatever it takes" (From the movie Mr. Mom) It's a range power companies try to maintain between approximately 220 and 240 volts. (My second favorite electrician's joke is what do you need to know to be a plumber? Answer: S*** flows downhill and payday is Friday...) Mine runs almost 250 volts here most times. Just checked it it is 246.5 VRMS right now. residential circuits are two wire, the third wire is a GROUNDIf they connect together in the breaker box, is this really safe? ... ... *** Ask the guys who write the national electric code. I am but their local servant. :-) Ground should be ground... The equipment connected and the service entrance should all be grounded. My original power service in this house 42 years ago was grounded to water pipes. Then "they" also found that water companies would remove water meters from time to time, so now it is required by code to jumper over the water meter to maintain ground during that service. Lost a few meter technicians over time I suppose. Plus now current code requires at the meter socket you have quantity two 5/8" 8 foot copper ground rods 6' apart outside grounding the meter socket. Plus if you use non-metallic conduit between the panel and meter socket you need to pull a ground wire through there. "They" (The Power Gods) want NEUTRAL which is provided by the power company to be kept as close to ground potential as possible. The power company does not provide you a GROUND, They don't provide you technically 220/240 either, they provide two circuits of out of phase 120 on either side of a neutral; it is your responsibility to provide the GROUND and quite if by magic you make 240 Volts inside your panel. Consumers make all sorts of assumptions... Where actually as the consumer you are making the various voltages to power your house by yourself. You provide the ground... Which is the return path for the power company's 7200 Volts. (They only ground every other pole usually) and You make 220/240 inside your panel by wiring the out of phase 120's together. If you look at it that way... With Joe ham wiring away in his box not understanding what's actually going on, How safe is that? Maybe Europe's 250 scenario is a lot safer to start with? The bonding strap in a power panel is about a 10 gauge aluminum strap is all. Which is adequate if you don't ask ground to carry any current from gear. I have never heard of one of those melting in half except after a lightning strike, but it could happen if you drew power acrossed it. BOB DD R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org Yahoo! Groups Links |
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Re: Inrush filament current protection
Robert B. Bonner
See below
________________________________________ From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of KR4DA Sent: Monday, November 13, 2006 10:31 AM To: ham_amplifiers@... Subject: Re: [ham_amplifiers] Re: Inrush filament current protection 210-250v depends on the utility company... My experience and I am not certified.... read any basic book on it..... I have done most of the wiring around my house.. a well and the pool and the 24x30 shop with welders etc..... up to 220v is not rocket science.. Should be four wires. 1. RED 120v one phase side 2.BLACK 120v one phase side 3. WHITE neutral 4.plain copper wire. **** Red and Black are both acceptable colors to use, they don't have to be one red and one black. You should be very careful if you get into 3 phase at all as they become different meanings. When in YES you can use the WHITE 120v BLACK 120v and the plain copper wire as GND. But you might confuse a person thinking this is a 110v wiring as white is NOT supposed to have 110v on it... WHITE is supposed to be NEUTRAL. **** You can pull a standard Romex line with white - black and bare ground wire, however where the white is exposed YOU MUST cover the white with Black tape to TELL SERVICE PEOPLE that this is the other leg of a 220/240 circuit. This is allowed. I do know they there is a chassis connection and a ground connection on some electorical devices where this is need I am not sure. I have seen some old TUBE stuff that required this. Usually the white and plain copper are connected together at the BOX. BUT the white has one bus bar and the plain copper has another. If you look in the power box the power company neutral is tied to a COMMAN BAR this is where the WHITES are connected... BUT then running from the power company neutral is usually another BAR going to a strip where the plain copper wires are attached. There is no actual really separation on these GND and neutral bars... It's a just do it this way thing. **** Yes you are correct there are separate busses in the panel. This is because neutral and ground are not supposed to be the same thing, however they are tied together. NEVER confuse them as the same thing as they are never the SAME even if they appear to be tied together. The white wire is a current carrying conductor and the green or bare is not. Is this over kill? Not if it saves your life. This is done to standardize power panels. Sure as S*** somebody here is going to pop a cover off a 3 phase panel someday and kill himself if he doesn't learn what things are and why... When you get into HIGHER more complicated phases of power 440 880v then the GND and NEUTRAL provided by the power company are critical. But not for 220v requirements. Incorrect, but this is the Consumer fallacy I'm trying to cure. *** Remember I've already said the power company doesn't provide GROUND you do. Its like GUNS don't kill people - People kill people.. While you can justify "They are all the Same" this is a poor justification. The rules of electricity are developed to kill as few people a year as possible. When you start treating things the same is when you will become a statistic. Let's respect the CORRECT definitions and uses of these conductors. (Whether I can convince you they are different or not) Some day your whole house will be full of ARC FAULT and GROUND FAULT Breakers. They are now becoming code... When that day comes you'll be in a world of hurt otherwise. BOB DD AKA "Electro the Magnificent" I didn't make that up BTW, I was dubbed that by a past employer. OH yeah and if you want a violent code argument I'll give you Don "The CODE" Coder's phone number he even drove me nuts with code discussions, I'm a pussy cat in comparison... :-) RB BWAAAHAHAHAHAHA! R L Measures wrote: On Nov 13, 2006, at 4:48 AM, Robert B. Bonner wrote: Jim,Is not 240v standard in the United States? residential circuits are two wire, the third wire is a GROUNDIf they connect together in the breaker box, is this really safe? ... ... R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org -- de KR4DA Bob Middleburg, FL HK0/KR4DA J79DA FG/KR4DA |
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Re: Inrush filament current protection
On Nov 13, 2006, at 8:30 AM, KR4DA wrote:
210-250v depends on the utility company...Not in California, it's set at 228v to 240v by the PUC. My experience and I am not certified....I do not believe everything in any book. I have done most of the wiring around my house.. a wellIt's required in this neck of the woods. BUT the white has one bus bar and the plain copper has another. If you look in the power box the power company neutral is tied to a COMMANI looked. In our breaker box, all the ground wires and all the Neutral wire connecct in one bus bar. How would it be different if there were two bus bars that are connected by a bus-wire? ...cheers, Bob R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org |
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Re: NOS cermic-metal tube burn in
What is the screen PS V?
What is the anode PS V? What Class? On Nov 13, 2006, at 7:34 AM, Hsu wrote: Hi, There are two Chinese FU-251F(4CX250B) cermic-metal tubes, they are new but storge for very long time. The output power only 200-250W( a pair), Could someone cal tell me how to solve this problem?Is it means I have to drop them in the junk box?R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org |
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Re: Inrush filament current protection
FRANCIS CARCIA
My building inspector did not want the ground wire in the meter socket. I ran conduit off the breaker panel to the rods. I also ran #4 over to the water main both sides of the meter. Then I showed him?the 4 #8s coming through the wall that go around the footing and through the yard. He smiled and said connect them also. Next I got some interesting lightning stories. gfz
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"Robert B. Bonner" wrote:
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Re: Inrush filament current protection
Robert B. Bonner
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-----Original Message-----
From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of R L Measures Sent: Monday, November 13, 2006 9:41 AM To: ham_amplifiers@... Subject: Re: [ham_amplifiers] Re: Inrush filament current protection On Nov 13, 2006, at 4:48 AM, Robert B. Bonner wrote: Jim,Is not 240v standard in the United States? *** You can call it whatever you want, there is no actual voltage 220-230-234-240.. So you will sometimes see it referenced 220/240 which is the correct term. Or my favorite inside electrician's joke "220-221 whatever it takes" (From the movie Mr. Mom) It's a range power companies try to maintain between approximately 220 and 240 volts. (My second favorite electrician's joke is what do you need to know to be a plumber? Answer: S*** flows downhill and payday is Friday...) Mine runs almost 250 volts here most times. Just checked it it is 246.5 VRMS right now. residential circuits are two wire, the third wire is a GROUNDIf they connect together in the breaker box, is this really safe? ... ... *** Ask the guys who write the national electric code. I am but their local servant. :-) Ground should be ground... The equipment connected and the service entrance should all be grounded. My original power service in this house 42 years ago was grounded to water pipes. Then "they" also found that water companies would remove water meters from time to time, so now it is required by code to jumper over the water meter to maintain ground during that service. Lost a few meter technicians over time I suppose. Plus now current code requires at the meter socket you have quantity two 5/8" 8 foot copper ground rods 6' apart outside grounding the meter socket. Plus if you use non-metallic conduit between the panel and meter socket you need to pull a ground wire through there. "They" (The Power Gods) want NEUTRAL which is provided by the power company to be kept as close to ground potential as possible. The power company does not provide you a GROUND, They don't provide you technically 220/240 either, they provide two circuits of out of phase 120 on either side of a neutral; it is your responsibility to provide the GROUND and quite if by magic you make 240 Volts inside your panel. Consumers make all sorts of assumptions... Where actually as the consumer you are making the various voltages to power your house by yourself. You provide the ground... Which is the return path for the power company's 7200 Volts. (They only ground every other pole usually) and You make 220/240 inside your panel by wiring the out of phase 120's together. If you look at it that way... With Joe ham wiring away in his box not understanding what's actually going on, How safe is that? Maybe Europe's 250 scenario is a lot safer to start with? The bonding strap in a power panel is about a 10 gauge aluminum strap is all. Which is adequate if you don't ask ground to carry any current from gear. I have never heard of one of those melting in half except after a lightning strike, but it could happen if you drew power acrossed it. BOB DD R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org Yahoo! Groups Links |
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Re: 3-500Z socket.... Johnson vs Eimac
Peter Voelpel
Rich,
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it says 0.082" at sea level and 500W dissipation 73 Peter -----Original Message-----
The Eimac spec sheet says 0.82" at sea level. |
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Re: Inrush filament current protection
KR4DA
开云体育210-250v depends on the utility company...My experience and I am not certified.... read any basic book on it..... I have done most of the wiring around my house.. a well and the pool and the 24x30 shop with welders etc..... up to 220v is not rocket science.. Should be four wires. 1. RED 120v one phase side 2.BLACK 120v one phase side 3. WHITE neutral 4.plain copper wire. When in YES you can use the WHITE 120v BLACK 120v and the plain copper wire as GND. But you might confuse a person thinking this is a 110v wiring as white is NOT supposed to have 110v on it... WHITE is supposed to be NEUTRAL. I do know they there is a chassis connection and a ground connection on some electorical devices where this is need I am not sure. I have seen some old TUBE stuff that required this. Usually the white and plain copper are connected together at the BOX. BUT the white has one bus bar and the plain copper has another. If you look in the power box the power company neutral is tied to a COMMAN BAR this is where the WHITES are connected... BUT then running from the power company neutral is usually another BAR going to a strip where the plain copper wires are attached. There is no actual really separation on these GND and neutral bars... It's a just do it this way thing. When you get into HIGHER more complicated phases of power 440 880v then the GND and NEUTRAL provided by the power company are critical. But not for 220v requirements. R L Measures wrote:
-- de KR4DA Bob Middleburg, FL HK0/KR4DA J79DA FG/KR4DA |
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Re: 3-500Z socket.... Johnson vs Eimac
On Nov 13, 2006, at 2:30 AM, pentalab wrote:
--- In ham_amplifiers@..., R L Measures <r@...> wrote:The Eimac spec sheet says 0.82" at sea level.requires a high-pressure centrifugal blower, and Ham amps used an And that's for 500/1000 w CCSOpinions count way less than manometer measurements. Heck......The nickels are glued down about 5" apart.corners along one edge is light enough to rise automatically withA square of varnished cardboard with two nickels glued to theflap that hinges up to let the air out. It just doesn't look as They are correct -- it's called Stephan's Law and the power radiatedred radiation?RICH SEZ... So objects that glow red-orange do not exhibit infra-### here's the interesting bit. Eimac states the glass tubescool by infared radiation.... well my natural gas fireplace puts is a function of the object's Temp raised to the 4th power. I can put my handsYou would have done somewhat better at this point had you put your hands on the mouse and clicked Send. . on theThe SB-220 has a ≈600W HV transformer. Hello! cheers, Jim .R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org |
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Re: "Father Measures"
On Nov 13, 2006, at 3:53 AM, pentalab wrote:
--- In ham_amplifiers@..., R L Measures <r@...> wrote:Hardly, Jim. I know too much about history to ever join any organized religion.make a good priest. Maybe they were joking?... cheers R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org |
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Re: Inrush filament current protection
On Nov 13, 2006, at 4:48 AM, Robert B. Bonner wrote:
Jim,Is not 240v standard in the United States? residential circuits are two wire, the third wire is a GROUNDIf they connect together in the breaker box, is this really safe? ... ... R L Measures, AG6K, 805.386.3734 r@..., rlm@..., www.somis.org |
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