Re: Inductive EHT filtering
I just did this recently.? I bought a used Dahl? choke (4H,? 3 amps CCS, and 15 kv rated). Weighs 127 lbs and uses the same hypersil core as the Dahl 10 kva plate xfmrs...which also weigh 127 lbs.? Bought it across town from a ham, who got it from the? old? satellite uplink station, just north of me The date code is 1991, and it's in pristine shape.? They had a total of 19 of em.?
It's called a? C-L-C? filter setup.? ? Basically? ?you take a regular? 'high C' standard B+? power supply, and add a choke in series with the B+...followed by a cap. In software, that's called adding a 'LC' section.? ?Mine is setup for 60 hz single phase. Modelling it all in software 1st (Duncan's PSUD-2), which does NOT handle 3 phase supplies, ( but will handle 50/60/400 hz single phase)... there are some? serious concerns, and caveats.? (You would probably need Spice, or LT-Spice, to handle 3 phase).
In software, it all goes to hell, and fast, IF the added cap after the choke ( let's call it? 'C2')? is not at least the same value as the main filter cap before the choke.? It should really be 50-100% bigger than the main? 'C1' filter cap.?
If the C2 is smaller than the C1 cap, what happens is you get this severe? yo-yoing... down-up-down-up-down-up output voltage waveform, until it finally settles down after 200-600 msecs, depending on values.? For something like say FM broadcast, non issue.? For? CW, and esp SSB, it's a real mess.? ?The 1st cap? (C1 cap) still gets hammered with the high AC ripple current, same as before the LC section is added.? ?The 2nd cap has extremely little rms current flowing into it.?
With any flashover, you still need a fast, HV fuse in series with the? final B+ output, followed by a HD glitch resistor.? ?( I had that before the LC section added).? ?I got the choke for minimal cost, and so it's just a good experiment I always wanted to try out.... more to verify the software than any practical use.? End result is, it's gross overkill for ripple reduction.? ?Mine has a 0db cut off of just 1.7 hz...and a 3 db cut off of only ( I think) 2.5 hz.? Ripple reduction at 120 hz (2F on? single phase) is -129 db.? ?My L4B with it's 25 uf filter cap (8 x 200uf caps in series) is only -30 db... and 2.9% ripple.... which is blatantly obvious on any RF monitor scope, drives me nuts.??
The added LC section gets better. The harmonics of 120 hz, (240-360-480 hz etc)? ?get killed at an even greater rate.? The added LC filter attenuates above it's cut off freq at a rate of? 12 db per octave.? ? I verified all this through measurements. The software is dead on.??
Ok, here's what you don't want to do,? and that's wire the choke in series with the B-.? ? Reason is, any V drop in the B- is just extra, yo-yoing extra, unwanted bias on the GG triode.? ?And that is in addition to the normal regulated bias on the tube.?
The V drop across the choke is simply the current through the choke? x DC resistance of the choke.? ?My 4H choke is 9.56 ohms when cold, and 10 ohms when warm.? I tested it with my small lab supply, and stuffed 3 amps? CCS through it for hrs...doesn't even get warm, stays at ambient room temp.? It does heat up with 6 amps through it.... and right where the gapped cores are.? ( it also becomes the mother of all electromagnets).? Crank the current up..and u will reach a point of thermal runaway.? ?With normal 2.6 to 3.0 amps of plate current through the 10 ohm? choke, = 25-30 vdc V drop.?
I tested a 2nd choke, a new? Hammond 1H choke, which is rated at 1000 ma CCS....and has a 5.75 ohm resistance.? ?I tested it with 800 ma though it, stone cold.? The Hammond is only rated for 1 kv ( 1.5 kv hi-pot test)..so it has to be installed in series with the? B+....AND well insulated from the chassis.? Treat it like a string of 450 vdc lytics.
?
Same deal on the big, 127 lb dahl choke.? ?It's wired in series with the B+, but well insulated from the chassis.? I used 4 x of those red...? HV glastic insulators, that come with threaded? 3/8" inserts in each end.? Choke sits on top of a pair of upside down aluminum U channel's....which are in turn? insulated? ( via 4 x glastics) from the? 1.5" thick plywood? base installed at the bottom of the rack.? ?Insulated from chassis, the V stand off is a non issue.? ?You will still get the normal V drop across the choke, but at least it's not adding bias to the cathode.?
On any single phase (60 hz) FWB / FWD? B+ supply,? the raw DC ( before any filter cap)? has? 67% ripple...and ripple freq is 120 hz ( 2F).
?On 3 phase, the raw DC? has? just 5.2% ripple.? ?On 3 phase, the ripple freq is 6F (300 hz in the UK, 360 hz in NA).? ?With 3 phase, your raw DC is not much worse vs the 2.9% ripple, after the 25 uf filter in my drake amps.?
IE: caps get charged up (or topped up as folks in the UK say) 100/120 times per second on single phase......and? 300/360 times per second on 3 phase.? ?That's the HUGE advantage of 3 phase power.?
?
Before you try the choke, measure it's DC resistance 1st..then model it in software.? ?And make sure it's not a swinging choke.? See if you can measure the choke on an LCR meter.? (peter told me eons ago, that with typ 3 phase B+ supplies,? a small filter cap was used, followed by the series choke...and no C2 cap).? The ripple is then down to zip.? If it works in software, it will work? in? the real world.? ?If your DC resistance on that 10H choke is high, like (as I suspect) in the 40-60 ohm range, any normal V drop across it, will be in addition to the V drop across any glitch resistor.?
?
With the typ series string of resistors used for the multiplier string for the B+? HV meter,? you can put the? DVM across the last resistor, or 2nd or 3rd to last resistor,? and measure the AC ripple component...with a full bore load applied.?
For my setup, for safety purposes...and to protect the choke,? I installed a HB adjustable spark gap across the choke terminals. Made from solid brass? 1/4-20 hardware, mounted on a pair of 3/4" x 3/4" x 1/6" thick aluminum angles.? Angles are mounted directly to the threaded studs on the choke.? Solid brass acorn nuts used where the gap resides.? Acorn nuts are semi domed, and ideal for this application.? If they get trashed, they are easily replaced.? ?Acorn nuts face each other.? Solid brass lock nuts are used to lock the gap into place....done with feeler gauges, and also a hi pot tester.? I also installed a surplus SPST Kilovac ceramic vac relay across the choke terminals.? I can shunt out the choke at any time, for testing purposes.?
Typ, with any B+ to grid arc, or say B+ to chassis arc, the 50 ohm glitch resistor will? LIMIT the fault current to just.... B+ / 50 ohms.? Meanwhile, the fast? HV fuse before the glitch resistor assy? will open off in < 1-2 msecs every time.? The C2 cap will discharge 1st...followed by the C1 main cap. When the C1 cap discharges, all that fault current flows through the choke... with a resulting MASSIVE V spike across the choke.? Chokes impede current ( both AC + DC) by dumping voltage.? I'm 95% convinced this is why chokes fail shorted to the frame in Henry radio amplifiers that use a resonant choke input.? You can also simulate the fault current in software...it's an eye opener.? This is a problem when chokes are wired in series with the B+.....and are not insulated from the chassis and / or no spark gap used.? ?The spark gap across the choke trick was used by Harris, and several others in the past.? ?I just re-invented the wheel.?
On software, you can see the normal negative / positive swing on the choke with normal plate current drawn, either CCS cxr, or up / down like CW / SSB.? ?Typ it's not very much, < 100 vdc.? ? The spark gap across the choke is dirt cheap to implement.?
?
Jim? ?VE7RF
|
Re: 8410/9500 Wattmeter Failure
There is an Alpha group here on "Groups.io", rather specific to the 9500, but I've seen inquiries regarding other Alpha models. In addition, Glenn Pladsen (AE0Q) often posts replies to issues posted there, and sometimes will email you direct regarding things posted on the forum.
The Alpha 9500 group is HERE: /g/Alpha9500
Good luck.-- 73,
~Alan
|
I've built many EHT supplies over decades but have always used capacitive only, ripple-filtering. Sitting below my desk for many years, is an inductor rated 7,500V, 0.85A CCS, 10 Henries. It came from an industrial RF heater. I've never seen one used in an EHT ham amplifier supply...has anyone experience of this? 10H, even with just 1uF after it, has a -3dB frequency of 50Hz, so it would be pretty effective at 300Hz (3-phase, full-wave ripple). But how would the inductive ripple filter respond with an SSB load? What happens if the tube flashes over? Are some extra protections required? Thanks Tim 
|
Re: Ameritron Plate Chokes
RFP will not sell 3-500Z tubes to overseas buyers but I bought 4
of them through their Ebay store, no problem. They will send them
anywhere in the world.
Go figure.
73, Alek VK6APK
On 19/02/2024 3:34 am, Dave w6de wrote:
toggle quoted message
Show quoted text
Thank
you for this write up.
?
73,
Dave,
w6de
?
?
On Sat, Feb 17, 2024 at 11:39 PM, Dave w6de
wrote:
What are the issues with Ameritron Plate
Chokes?
I have used an RF Parts look alike for several amplifier
projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer
available for export."
When I worked for a US Defense Contractor, I found that
Great Britain, Australia, and New Zealand were exempt from
these restrictions.
It may be worth an inquiry to see if RF-Parts will recognize
this.
Note: the RFC3 plate choke resonates at 10 MHz, and the
Ameritron High Power Tube Amplifiers are not specified to
run on the 10 MHz (30 Meters) band.
73,
Dave, w6de
##? No they don't.? I just recently bought 2 x of the
ameritron chokes from? RF parts. ( 2-3 yrs ago).? ?ONLY on
some selected items, ( and that choke is NOT one of em, as of
5 mins ago) will they refuse to ship outside the USA.? I had
also ordered a pair of 0-4.4 uh roller coils. RF parts would
not export em.? I couldn't even get em shipped to a friend in
the usa.? ?The only work around was to have a friend in the
usa pay for em, and have em shipped to his usa address.....
then re-send em to my address via USPS. ..( that advice came
from the girl in the office, not the owner, bonny)
?
## merrit Arnold's wife and son now run RF parts.? One of the
girls who works there tells me arnolds wife is a ...'real
piece of work'.? ?I know other folks who wanted to buy 4x10
tubes..and that was another item they would not ship
overseas.? Bonny has some bug up her rear end, about some
items that should not be shipped outside of the
usa...siting....'only should be sold in america'.? The small
0-4.4 uh roller coil ( 8 ga wire) was originally made by
multronics.? ?Then Cardwell condenser co? bought out
multronics...and the same roller coils in the RF parts site
were indeed stamped...'Cardwell condenser Corp'.? ?Cardwell
sold out to 'Viking'? ?( who owns the custom clothing line).?
?I just ordered 2 of the rollers? directly from Viking, no
fuss, shipped fast.?
?
## never had any issues, ordering anything from the usa,
never.? ?And ZERO issues with customs...items sail right to my
front door.? Only the 'select items'? on RF parts site.? ?IMO,
just another goofball outfit that I can't throw money at.?
?
##? I just tested both ameritron chokes on my VNA last week.?
?They resonate at? ?12.332 mhz....and also? 16.247 mhz.? ?They
will not blow up on any of the 9 x ham bands.? ?They won't
blow up on 60m band, and also 11 m.??
They will blow up on those 2 x freqs I stated,? +/-? 750
khz.?
?
## However, I know of at least 12 of em now, that have blown
up in the last few years..... typ on 17m.?
##? W8JI sez he used to hand wind em on his machine, in his
own shop...for use in all the Ameritron amps.? ?They have to
be carefully wound, and using the same magnet wire, and
correct placement of gaps, correct turns count on all 3 x
windings, and also correct amount of? that clear...'goop'?
they slop on the sides, to keep the winding intact.? Magnet
wire comes in 4 x different thickness's of enamel / formvar /
nyclad? etc...and for each gauge.? You can also buy magnet
wire in 1/2 gauges.? You can also buy magnet wire in several
different temp ratings...and also several different V
ratings.? ?Depending on type of insulation used, and
thickness,? that alone will change the dielectric constant.?
##? Depending on which of the 4 x? thickness'? used,? etc,? it
can easily shift the 2 x series resonance freqs.? ?Get the
gaps wrong, and they will shift again.? Slop too much/too
little clear goop on the sides of the windings, and it shifts
again.?
## JI sez he left ameritron in 2019. ( KM1H said JI got
fired, but u know carl). After JI left, ameritron started?
winding their own chokes....and it's a disaster.? JI said he
had a ham ship? him an ameritron amp in for repair, ( made
after 2019)? and? immediately saw that the plate choke is a?
screwed up dog's breakfast.? He said he has seen that several
times now.? He also said the gap between bottom winding,...and
the chassis is way too close? vs his original version.?
?
## watch out.? Alpha copied the ameritron choke, and make
their own version, which looks identical.... and works.? ?RF
parts used to sell the alpha version, then switched to only
the ameritron version, which is still screwed up.? How the
hell they got the? 16.247 mhz? up higher towards the 17m band
is beyond me.?
?
## W8JI now refuses to work on ANY ameritron amp, tube or
ss.? ?He does sell the original version of the plate choke,
built and tested to correct specs.? ?He makes the chokes in
his shop, same as before 2019.?
?
## These days, I would check any plate choke on the vna,
since they are so cheap (vna).?
|
Re: Ameritron Plate Chokes
There are? Russian 4?H roller inductors..
They are available at Dr. Alex, UR4LL:
?
?
73
Peter, DJ7WW
?
?
## merrit Arnold's wife and son now run RF parts.? One of the girls who works there tells me arnolds wife is a ...'real piece of work'.? ?I know other folks who wanted to buy 4x10 tubes..and that was another item they would not ship overseas.? Bonny has some bug up her rear end, about some items that should not be shipped outside of the usa...siting....'only should be sold in america'.? The small 0-4.4 uh roller coil ( 8 ga wire) was originally made by multronics.? ?Then Cardwell condenser co? bought out multronics...and the same roller coils in the RF parts site were indeed stamped...'Cardwell condenser Corp'.? ?Cardwell sold out to 'Viking'? ?( who owns the custom clothing line).? ?I just ordered 2 of the rollers? directly from Viking, no fuss, shipped fast.?
?
?
|
Re: Ameritron Plate Chokes
Thank you for this write up.
?
73,
Dave, w6de
?
toggle quoted message
Show quoted text
From: [email protected]
<[email protected]> On Behalf Of Jim VE7RF via groups.io
Sent: 18 February, 2024 17:22
To: [email protected]
Subject: Re: [ham-amplifiers] Ameritron Plate Chokes
?
On Sat, Feb 17, 2024 at 11:39 PM, Dave w6de wrote:
What are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer available for export."
When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions.
It may be worth an inquiry to see if RF-Parts will recognize this.
Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band.
73,
Dave, w6de
##? No they don't.? I just recently bought 2 x of the ameritron chokes from? RF parts. ( 2-3 yrs ago).? ?ONLY on some selected items, ( and that choke is NOT one of em, as of 5 mins ago) will they refuse to ship outside the USA.? I had also ordered a pair
of 0-4.4 uh roller coils. RF parts would not export em.? I couldn't even get em shipped to a friend in the usa.? ?The only work around was to have a friend in the usa pay for em, and have em shipped to his usa address..... then re-send em to my address via
USPS. ..( that advice came from the girl in the office, not the owner, bonny)
?
## merrit Arnold's wife and son now run RF parts.? One of the girls who works there tells me arnolds wife is a ...'real piece of work'.? ?I know other folks who wanted to buy 4x10 tubes..and that was another item they would not ship overseas.? Bonny has
some bug up her rear end, about some items that should not be shipped outside of the usa...siting....'only should be sold in america'.? The small 0-4.4 uh roller coil ( 8 ga wire) was originally made by multronics.? ?Then Cardwell condenser co? bought out
multronics...and the same roller coils in the RF parts site were indeed stamped...'Cardwell condenser Corp'.? ?Cardwell sold out to 'Viking'? ?( who owns the custom clothing line).? ?I just ordered 2 of the rollers? directly from Viking, no fuss, shipped fast.?
?
## never had any issues, ordering anything from the usa, never.? ?And ZERO issues with customs...items sail right to my front door.? Only the 'select items'? on RF parts site.? ?IMO, just another goofball outfit that I can't throw money at.?
?
##? I just tested both ameritron chokes on my VNA last week.? ?They resonate at? ?12.332 mhz....and also? 16.247 mhz.? ?They will not blow up on any of the 9 x ham bands.? ?They won't blow up on 60m band, and also 11 m.??
They will blow up on those 2 x freqs I stated,? +/-? 750 khz.?
?
## However, I know of at least 12 of em now, that have blown up in the last few years..... typ on 17m.?
##? W8JI sez he used to hand wind em on his machine, in his own shop...for use in all the Ameritron amps.? ?They have to be carefully wound, and using the same magnet wire, and correct placement of gaps, correct turns count on all 3 x windings, and also
correct amount of? that clear...'goop'? they slop on the sides, to keep the winding intact.? Magnet wire comes in 4 x different thickness's of enamel / formvar / nyclad? etc...and for each gauge.? You can also buy magnet wire in 1/2 gauges.? You can also buy
magnet wire in several different temp ratings...and also several different V ratings.? ?Depending on type of insulation used, and thickness,? that alone will change the dielectric constant.?
##? Depending on which of the 4 x? thickness'? used,? etc,? it can easily shift the 2 x series resonance freqs.? ?Get the gaps wrong, and they will shift again.? Slop too much/too little clear goop on the sides of the windings, and it shifts again.?
## JI sez he left ameritron in 2019. ( KM1H said JI got fired, but u know carl). After JI left, ameritron started? winding their own chokes....and it's a disaster.? JI said he had a ham ship? him an ameritron amp in for repair, ( made after 2019)? and? immediately
saw that the plate choke is a? screwed up dog's breakfast.? He said he has seen that several times now.? He also said the gap between bottom winding,...and the chassis is way too close? vs his original version.?
?
## watch out.? Alpha copied the ameritron choke, and make their own version, which looks identical.... and works.? ?RF parts used to sell the alpha version, then switched to only the ameritron version, which is still screwed up.? How the hell they got the?
16.247 mhz? up higher towards the 17m band is beyond me.?
?
## W8JI now refuses to work on ANY ameritron amp, tube or ss.? ?He does sell the original version of the plate choke, built and tested to correct specs.? ?He makes the chokes in his shop, same as before 2019.?
?
## These days, I would check any plate choke on the vna, since they are so cheap (vna).?
|
Re: Ameritron Plate Chokes
On Sat, Feb 17, 2024 at 11:39 PM, Dave w6de wrote:
What are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer available for export."
When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions.
It may be worth an inquiry to see if RF-Parts will recognize this.
Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band.
73,
Dave, w6de
##? No they don't.? I just recently bought 2 x of the ameritron chokes from? RF parts. ( 2-3 yrs ago).? ?ONLY on some selected items, ( and that choke is NOT one of em, as of 5 mins ago) will they refuse to ship outside the USA.? I had also ordered a pair of 0-4.4 uh roller coils. RF parts would not export em.? I couldn't even get em shipped to a friend in the usa.? ?The only work around was to have a friend in the usa pay for em, and have em shipped to his usa address..... then re-send em to my address via USPS. ..( that advice came from the girl in the office, not the owner, bonny)
?
## merrit Arnold's wife and son now run RF parts.? One of the girls who works there tells me arnolds wife is a ...'real piece of work'.? ?I know other folks who wanted to buy 4x10 tubes..and that was another item they would not ship overseas.? Bonny has some bug up her rear end, about some items that should not be shipped outside of the usa...siting....'only should be sold in america'.? The small 0-4.4 uh roller coil ( 8 ga wire) was originally made by multronics.? ?Then Cardwell condenser co? bought out multronics...and the same roller coils in the RF parts site were indeed stamped...'Cardwell condenser Corp'.? ?Cardwell sold out to 'Viking'? ?( who owns the custom clothing line).? ?I just ordered 2 of the rollers? directly from Viking, no fuss, shipped fast.?
?
## never had any issues, ordering anything from the usa, never.? ?And ZERO issues with customs...items sail right to my front door.? Only the 'select items'? on RF parts site.? ?IMO, just another goofball outfit that I can't throw money at.?
?
##? I just tested both ameritron chokes on my VNA last week.? ?They resonate at? ?12.332 mhz....and also? 16.247 mhz.? ?They will not blow up on any of the 9 x ham bands.? ?They won't blow up on 60m band, and also 11 m.??
They will blow up on those 2 x freqs I stated,? +/-? 750 khz.?
?
## However, I know of at least 12 of em now, that have blown up in the last few years..... typ on 17m.?
##? W8JI sez he used to hand wind em on his machine, in his own shop...for use in all the Ameritron amps.? ?They have to be carefully wound, and using the same magnet wire, and correct placement of gaps, correct turns count on all 3 x windings, and also correct amount of? that clear...'goop'? they slop on the sides, to keep the winding intact.? Magnet wire comes in 4 x different thickness's of enamel / formvar / nyclad? etc...and for each gauge.? You can also buy magnet wire in 1/2 gauges.? You can also buy magnet wire in several different temp ratings...and also several different V ratings.? ?Depending on type of insulation used, and thickness,? that alone will change the dielectric constant.?
##? Depending on which of the 4 x? thickness'? used,? etc,? it can easily shift the 2 x series resonance freqs.? ?Get the gaps wrong, and they will shift again.? Slop too much/too little clear goop on the sides of the windings, and it shifts again.?
## JI sez he left ameritron in 2019. ( KM1H said JI got fired, but u know carl). After JI left, ameritron started? winding their own chokes....and it's a disaster.? JI said he had a ham ship? him an ameritron amp in for repair, ( made after 2019)? and? immediately saw that the plate choke is a? screwed up dog's breakfast.? He said he has seen that several times now.? He also said the gap between bottom winding,...and the chassis is way too close? vs his original version.?
?
## watch out.? Alpha copied the ameritron choke, and make their own version, which looks identical.... and works.? ?RF parts used to sell the alpha version, then switched to only the ameritron version, which is still screwed up.? How the hell they got the? 16.247 mhz? up higher towards the 17m band is beyond me.?
?
## W8JI now refuses to work on ANY ameritron amp, tube or ss.? ?He does sell the original version of the plate choke, built and tested to correct specs.? ?He makes the chokes in his shop, same as before 2019.?
?
## These days, I would check any plate choke on the vna, since they are so cheap (vna).?
|
Re: Ameritron Plate Chokes
Almost every plate choke I see in an ameritron that comes in for repair is not wound properly. I always ask if they had used on 17 meters when I see a fried one , answer is always yes.
I tell everyone to stay of 17 , some listen and some don¡¯t. Ones that don¡¯t listen say they don¡¯t see anything online about issues on 17 meters.
The plate choke issue with 17 used to be posted in numerous places, but now seems to have vanished.
toggle quoted message
Show quoted text
On 2024-02-17 18:22, Alek Petkovic via groups.io wrote: Thanks Robert. There are numerous reports that a batch of the chokes
were burning up on 17m.
Anyway, problem solved, I have emailed W8JI with a view of purchasing
a few of his.
73, Alek VK6APK
On 18/02/2024 9:02 am, Robert W5AJ wrote:
Interesting
I've installed the RFC3 in AL82, RFParts 3-500 with 1600w out into
Navy surplus dummy load. Tested ALL bands including warc. Never
noticed an issue. Solid.
Same with Alpha 89 with RFC3 replacement. Worked great, sold the
Alpha.
I plan on using RFC3 in next HF homebrew.
Robert W5AJ
On Sat, Feb 17, 2024, 3:39 PM Dave w6de <w6de@...> wrote:
What are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer
available for export."
When I worked for a US Defense Contractor, I found that Great
Britain, Australia, and New Zealand were exempt from these
restrictions.
It may be worth an inquiry to see if RF-Parts will recognize this.
Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron
High Power Tube Amplifiers are not specified to run on the 10 MHz
(30 Meters) band.
73,
Dave, w6de
-----Original Message-----
From: [email protected] <[email protected]> On
Behalf Of Alek Petkovic via groups.io [1]
Sent: 17 February, 2024 02:31
To: [email protected]
Subject: [ham-amplifiers] Ameritron Plate Chokes
Does anyone know if Ameritron have resolved the issues with their
spare parts plate chokes?
I would be interested in purchasing a couple if they are not going
to burn up.
73, Alek VK6APK. Links:
------
[1]
[2] /g/ham-amplifiers/message/40230
[3] /mt/104406328/8135091
[4] /g/ham-amplifiers/post
[5] /g/ham-amplifiers/editsub/8135091
[6] /g/ham-amplifiers/leave/12941173/8135091/773995006/xyzzy
|
Re: Ameritron Plate Chokes
Dunno mate. we're pretty much accustomed to paying double for
everything in this part of the world, so we don't worry too much
about it.
Guess I'll hear from Tom when he fronts for work this week.
Cheers, Alek.
On 18/02/2024 1:11 pm, Bob wrote:
toggle quoted message
Show quoted text
Alek, How much will it be for them to be shipped
to you?
Bob W4JFA?
Thanks Robert. There are numerous reports that a batch of
the chokes were burning up on 17m.
Anyway, problem solved, I have emailed W8JI with a view
of purchasing a few of his.
73, Alek VK6APK
On 18/02/2024 9:02 am, Robert W5AJ wrote:
Interesting
I've installed the RFC3 in AL82, RFParts
3-500 with 1600w out into Navy surplus dummy load.?
Tested ALL bands including warc.? Never noticed an
issue.? ?Solid.
Same with Alpha 89 with RFC3
replacement.? Worked great, sold the Alpha.
I plan on using RFC3 in next HF
homebrew.
Robert W5AJ?
On Sat, Feb 17, 2024,
3:39 PM Dave w6de < w6de@...>
wrote:
What
are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several
amplifier projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No
longer available for export."
When I worked for a US Defense Contractor, I found
that Great Britain, Australia, and New Zealand were
exempt from these restrictions.?
It may be worth an inquiry to see if RF-Parts will
recognize this.
Note: the RFC3 plate choke resonates at 10 MHz, and
the Ameritron High Power Tube Amplifiers are not
specified to run on the 10 MHz (30 Meters) band.
73,
Dave, w6de
-----Original Message-----
From: [email protected]
<[email protected]>
On Behalf Of Alek Petkovic via
Sent: 17 February, 2024 02:31
To: [email protected]
Subject: [ham-amplifiers] Ameritron Plate Chokes
Does anyone know if Ameritron have resolved the issues
with their spare parts plate chokes?
I would be interested in purchasing a couple if they
are not going to burn up.
73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
Alek, How much will it be for them to be shipped to you? Bob W4JFA?
Thanks Robert. There are numerous reports that a batch of the
chokes were burning up on 17m.
Anyway, problem solved, I have emailed W8JI with a view of
purchasing a few of his.
73, Alek VK6APK
On 18/02/2024 9:02 am, Robert W5AJ
wrote:
Interesting
I've installed the RFC3 in AL82, RFParts 3-500
with 1600w out into Navy surplus dummy load.? Tested ALL bands
including warc.? Never noticed an issue.? ?Solid.
Same with Alpha 89 with RFC3 replacement.?
Worked great, sold the Alpha.
I plan on using RFC3 in next HF homebrew.
Robert W5AJ?
On Sat, Feb 17, 2024, 3:39 PM
Dave w6de < w6de@...>
wrote:
What
are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier
projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer
available for export."
When I worked for a US Defense Contractor, I found that Great
Britain, Australia, and New Zealand were exempt from these
restrictions.?
It may be worth an inquiry to see if RF-Parts will recognize
this.
Note: the RFC3 plate choke resonates at 10 MHz, and the
Ameritron High Power Tube Amplifiers are not specified to run
on the 10 MHz (30 Meters) band.
73,
Dave, w6de
-----Original Message-----
From: [email protected]
<[email protected]>
On Behalf Of Alek Petkovic via
Sent: 17 February, 2024 02:31
To: [email protected]
Subject: [ham-amplifiers] Ameritron Plate Chokes
Does anyone know if Ameritron have resolved the issues with
their spare parts plate chokes?
I would be interested in purchasing a couple if they are not
going to burn up.
73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
Merrit Arnold¡¯s wife took over and lots changed. I send my customers to penta now have for months. If ever a tube issue replacement is quick.
Nothing against rf parts , my customers get the whole sale price on tubes and east warranty replacement . Win win for my customers.
I what¡¯s best for my customers
toggle quoted message
Show quoted text
On 2024-02-17 17:41, Dave w6de wrote: It is probably because of the paperwork blizzard to send something when customs are involved. It appears to be different for each country. I personally have only sent things to Canada and Australia. Canada was easy via the postal service. But it was a mountain of paperwork to send a collector car to Australia (via ship). And, then just to send a spare set of keys and car history paperwork via the post/mail for the car, it was amazing how much paperwork was required--besides the amazing cost for just a large envelope.
73,
Dave, w6de
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of John Sparkes via groups.io
Sent: 17 February, 2024 23:59
To: [email protected]
Subject: Re: [ham-amplifiers] Ameritron Plate Chokes
Is it because you just can't see us from up there...?
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Mike Santas
Sent: Sunday, February 18, 2024 7:19 AM
To: [email protected]
Subject: Re: [ham-amplifiers] Ameritron Plate Chokes
Dave,
I don't think it's an ITAR issue......
73
Mike N2LYM
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Dave w6de
Sent: Saturday, February 17, 2024 5:40 PM
To: [email protected]
Subject: Re: [ham-amplifiers] Ameritron Plate Chokes
What are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer available for export."
When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions.
It may be worth an inquiry to see if RF-Parts will recognize this.
Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band.
73,
Dave, w6de
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Alek Petkovic via groups.io
Sent: 17 February, 2024 02:31
To: [email protected]
Subject: [ham-amplifiers] Ameritron Plate Chokes
Does anyone know if Ameritron have resolved the issues with their spare parts plate chokes?
I would be interested in purchasing a couple if they are not going to burn up.
73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
Thanks Robert. There are numerous reports that a batch of the
chokes were burning up on 17m.
Anyway, problem solved, I have emailed W8JI with a view of
purchasing a few of his.
73, Alek VK6APK
On 18/02/2024 9:02 am, Robert W5AJ
wrote:
toggle quoted message
Show quoted text
Interesting
I've installed the RFC3 in AL82, RFParts 3-500
with 1600w out into Navy surplus dummy load.? Tested ALL bands
including warc.? Never noticed an issue.? ?Solid.
Same with Alpha 89 with RFC3 replacement.?
Worked great, sold the Alpha.
I plan on using RFC3 in next HF homebrew.
Robert W5AJ?
On Sat, Feb 17, 2024, 3:39 PM
Dave w6de < w6de@...>
wrote:
What
are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier
projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer
available for export."
When I worked for a US Defense Contractor, I found that Great
Britain, Australia, and New Zealand were exempt from these
restrictions.?
It may be worth an inquiry to see if RF-Parts will recognize
this.
Note: the RFC3 plate choke resonates at 10 MHz, and the
Ameritron High Power Tube Amplifiers are not specified to run
on the 10 MHz (30 Meters) band.
73,
Dave, w6de
-----Original Message-----
From: [email protected]
<[email protected]>
On Behalf Of Alek Petkovic via
Sent: 17 February, 2024 02:31
To: [email protected]
Subject: [ham-amplifiers] Ameritron Plate Chokes
Does anyone know if Ameritron have resolved the issues with
their spare parts plate chokes?
I would be interested in purchasing a couple if they are not
going to burn up.
73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
Interesting
I've installed the RFC3 in AL82, RFParts 3-500 with 1600w out into Navy surplus dummy load.? Tested ALL bands including warc.? Never noticed an issue.? ?Solid.
Same with Alpha 89 with RFC3 replacement.? Worked great, sold the Alpha.
I plan on using RFC3 in next HF homebrew.
Robert W5AJ?
On Sat, Feb 17, 2024, 3:39 PM Dave w6de < w6de@...> wrote: What are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer available for export."
When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions.?
It may be worth an inquiry to see if RF-Parts will recognize this.
Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band.
73,
Dave, w6de
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Alek Petkovic via
Sent: 17 February, 2024 02:31
To: [email protected]
Subject: [ham-amplifiers] Ameritron Plate Chokes
Does anyone know if Ameritron have resolved the issues with their spare parts plate chokes?
I would be interested in purchasing a couple if they are not going to burn up.
73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
It is probably because of the paperwork blizzard to send something when customs are involved. It appears to be different for each country. I personally have only sent things to Canada and Australia. Canada was easy via the postal service. But it was a mountain of paperwork to send a collector car to Australia (via ship). And, then just to send a spare set of keys and car history paperwork via the post/mail for the car, it was amazing how much paperwork was required--besides the amazing cost for just a large envelope.
73,
Dave, w6de
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of John Sparkes via groups.io Sent: 17 February, 2024 23:59 To: [email protected]Subject: Re: [ham-amplifiers] Ameritron Plate Chokes Is it because you just can't see us from up there...? -----Original Message----- From: [email protected] < [email protected]> On Behalf Of Mike Santas Sent: Sunday, February 18, 2024 7:19 AM To: [email protected]Subject: Re: [ham-amplifiers] Ameritron Plate Chokes Dave, I don't think it's an ITAR issue...... 73 Mike N2LYM -----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Dave w6de Sent: Saturday, February 17, 2024 5:40 PM To: [email protected]Subject: Re: [ham-amplifiers] Ameritron Plate Chokes What are the issues with Ameritron Plate Chokes? I have used an RF Parts look alike for several amplifier projects. More chokes here Unfortunately, RF-Parts now lists these parts as "No longer available for export." When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions. It may be worth an inquiry to see if RF-Parts will recognize this. Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band. 73, Dave, w6de -----Original Message----- From: [email protected] < [email protected]> On Behalf Of Alek Petkovic via groups.io Sent: 17 February, 2024 02:31 To: [email protected]Subject: [ham-amplifiers] Ameritron Plate Chokes Does anyone know if Ameritron have resolved the issues with their spare parts plate chokes? I would be interested in purchasing a couple if they are not going to burn up. 73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
Is it because you just can't see us from up there...?
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Mike Santas Sent: Sunday, February 18, 2024 7:19 AM To: [email protected]Subject: Re: [ham-amplifiers] Ameritron Plate Chokes Dave, I don't think it's an ITAR issue...... 73 Mike N2LYM -----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Dave w6de Sent: Saturday, February 17, 2024 5:40 PM To: [email protected]Subject: Re: [ham-amplifiers] Ameritron Plate Chokes What are the issues with Ameritron Plate Chokes? I have used an RF Parts look alike for several amplifier projects. More chokes here Unfortunately, RF-Parts now lists these parts as "No longer available for export." When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions. It may be worth an inquiry to see if RF-Parts will recognize this. Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band. 73, Dave, w6de -----Original Message----- From: [email protected] < [email protected]> On Behalf Of Alek Petkovic via groups.io Sent: 17 February, 2024 02:31 To: [email protected]Subject: [ham-amplifiers] Ameritron Plate Chokes Does anyone know if Ameritron have resolved the issues with their spare parts plate chokes? I would be interested in purchasing a couple if they are not going to burn up. 73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
Dave,
I don't think it's an ITAR issue......
73
Mike N2LYM
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Dave w6de Sent: Saturday, February 17, 2024 5:40 PM To: [email protected]Subject: Re: [ham-amplifiers] Ameritron Plate Chokes What are the issues with Ameritron Plate Chokes? I have used an RF Parts look alike for several amplifier projects. More chokes here Unfortunately, RF-Parts now lists these parts as "No longer available for export." When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions. It may be worth an inquiry to see if RF-Parts will recognize this. Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band. 73, Dave, w6de -----Original Message----- From: [email protected] < [email protected]> On Behalf Of Alek Petkovic via groups.io Sent: 17 February, 2024 02:31 To: [email protected]Subject: [ham-amplifiers] Ameritron Plate Chokes Does anyone know if Ameritron have resolved the issues with their spare parts plate chokes? I would be interested in purchasing a couple if they are not going to burn up. 73, Alek VK6APK.
|
Re: Ameritron Plate Chokes
What are the issues with Ameritron Plate Chokes?
I have used an RF Parts look alike for several amplifier projects.
More chokes here
Unfortunately, RF-Parts now lists these parts as "No longer available for export."
When I worked for a US Defense Contractor, I found that Great Britain, Australia, and New Zealand were exempt from these restrictions.
It may be worth an inquiry to see if RF-Parts will recognize this.
Note: the RFC3 plate choke resonates at 10 MHz, and the Ameritron High Power Tube Amplifiers are not specified to run on the 10 MHz (30 Meters) band.
73,
Dave, w6de
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Alek Petkovic via groups.io Sent: 17 February, 2024 02:31 To: [email protected]Subject: [ham-amplifiers] Ameritron Plate Chokes Does anyone know if Ameritron have resolved the issues with their spare parts plate chokes? I would be interested in purchasing a couple if they are not going to burn up. 73, Alek VK6APK.
|
Does anyone know if Ameritron have resolved the issues with their spare parts plate chokes?
I would be interested in purchasing a couple if they are not going to burn up.
73, Alek VK6APK.
|
Re: Loaded Plate chokes...again
And they are using this 88uh loaded plate choke in the normal place... at the anode ???
|
Re: Loaded Plate chokes...again
This one:
?
?
73
Peter
?
?
?
-----Original-Nachricht-----
Betreff: Re: [ham-amplifiers] Loaded Plate chokes...again
Datum: 2024-02-16T16:34:06+0100
Von: "Jim VE7RF" <jim.thom@...>
An: "[email protected]" <[email protected]>
?
?
?
Where is the? 88 uh...down at the bottom ???
?
|
Alan - W5ARM
Bob
Robert, W5AJ