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46  eHam Forums / Site Talk / RE: eHam forums vs. QRZ forums on: March 25, 2013, 03:46:11 PM
at least we have generally been introduced to high-quality websites by some of the more erudite posters.  I certainly have one in mind...
47  eHam Forums / Company Reviews / RE: Kanga US on: March 24, 2013, 07:14:12 PM
bad run of luck, their sailboat got lightning-struck on the lake and wiped out last year.  that was pretty much last post on the website.

we had a tech back after a stroke at work half-time in about 4 months and he's back full time, in one of the most demanding sections.

wish him well.  this is surviveable.
48  eHam Forums / Boat Anchors / RE: Heathkit SB-102 troubles on: March 24, 2013, 07:11:06 PM
on the tubed HW/SB transceivers, every 22K resistor going to a tube plate is highly suspect, as are the bias and coupling resistors in the power amp areas.  I have replaced some 22Ks that went up to 80K.  shotgun 'em and uprate to 1 watt.  there is a Heath service note to uprate the 22K at the tube driving the AGC/meter circuit with a 2 watter.

no carbon comps, please, use metal film if it's not carrying RF, carbon film will replace everything.
49  eHam Forums / Elmers / RE: Davis Vantage Pro weather station repair on: March 17, 2013, 02:42:14 PM
123As are used in some remote controls, like Christmas light controllers and old garage door transmitters, you can find them in 1 and 2 packs at any home center.  if you build some of the signal tracer kits out there, they also use 123A batteries.

everything I have to replace, I keep spares on hand.  if I get one or two, they get used before they expire.
50  eHam Forums / Elmers / RE: Flux core or rosin core solder? on: March 14, 2013, 02:05:07 PM
Kester also makes industrial solders with acid flux, usually zinc chloride.

very double-plus-ungood for electronics, does the old ultraviolence on them.

do read the fine print
51  eHam Forums / Boat Anchors / RE: 323b thyratrons on: March 14, 2013, 02:00:53 PM
I was not aware that Heathkits used WE thyratrons.  geez, I'd have paid money for one of those
52  eHam Forums / RFI / EMI / RE: MFJ-1026 On the way, hookup suggestions? on: March 14, 2013, 10:38:08 AM
have not had to get one, remarkably quiet (so the antenna is probably not high enough here.)

but the 1025/1026/timewave systems are noise cancellation by addition to a second antenna.  several past threads indicate you are going to have to fool around with the noise detection antenna type and position, and twitch the knobs just so, to cancel noise.  it works when you use it right.  see w8ji for more

http://www.w8ji.com/mfj-1025_1026.htm
53  eHam Forums / Boat Anchors / RE: 323b thyratrons on: March 14, 2013, 10:19:44 AM
allegedly 15 of them here at $25

http://www.vacuumtubesinc.com/Products/AudioTubes/NewAudioandWesternElectricTubes.aspx
54  eHam Forums / Elmers / RE: My ignorance is showing, antenna tuner on: March 10, 2013, 12:10:15 PM
fun physics question:  if you use a tuner to provide a 1.01/1 match to a transciever, and the antenna remains a 5:1 bad match, where do the extra numbers go that aren't on the meter any more?  you can't create or destroy energy, after all, you can just transform it with some losses in the translation.

fun physics answer:  the rest warms the shack.  the antenna doesn't get any better, the tuner just allows the lumped load to accept your transmit power.  more power into a bad antenna?  nope, the antenna is still a 5:1 behind the curtain.  all that additional power is dissipated in heat within the tuner.

which is why people kvetch about tuners arcing and blowing up when "I only have 100 watts, and the tuner is rated at 300."

you receive better because you have a better match, and the microvolts come to you... but not as many as if you had a perfect dipole on tune for that frequency.  you transmit better, albeit a couple dB down, because your watts are not burning up in the feedline and in the final stage of the transceiver.  you limit burning up watts at the tuner, but you can load it better, so there is sum total more amps in the antenna.

there is still no Special Freakin' Magic here.  you reduce the losses and move most of the waste into the tuner.
55  eHam Forums / RFI / EMI / RE: Samsung HDTV and 40M on: March 08, 2013, 09:03:01 AM
if any of you ever built the Heathkit touch switch, you know how these work.  for the rest... you have a high megohm resistive network on a CMOS gate to pretend it's protected from static whacks.  the rest is stray AC picked up by your body that flops the state of the gate over.

and the pickup disc was attached to about a 3 foot wire.

I imagine the LCD TV pickups aren't set up with the divider network because they're behind the glass protection panel.  I also imagine there isn't enough lead length to put a ferrite over, and a bypass cap would desensitize it so much you might as well unplug the sensor board.  but I bet if the manufacturers cared, they could put a SMD inductor in series.
56  eHam Forums / Elmers / RE: Vacuum tube identification. on: March 07, 2013, 11:27:24 AM
KE3WD, I lost a post in this thread, too.  it was not exactly wisdom from God, so I'm not upset.  likely issue is they had a server issue of one type or another... lost it during a resync or backup, VM went down at a hoster shortly after posting and it wasn't out of cache, whatever.

but the upshot was if you can identify one tube of type X, then you can stare and compare to group its kin, but double-check in the tube tester to make sure the pins match up inside.  plenty of AF/RF pentodes look the same but are wired way different.
57  eHam Forums / Misc / RE: FCC cleaning up 14.313? on: March 06, 2013, 10:37:51 AM
FCC fines and orders, like putting IRS forms in post offices and libraries, only work if you are planning on being a good citizen.  flashing a badge, with a US Marshal flashing his badge, and loading the equipment in the trunk of the government van is going to do a lot more.

assuming... (1) they can spare the inspectors to confiscate, (2) they can spare the back-room staff to process the complaints or the observations, (3) they give a rip.

when was the last time a radio raconteur got parked on the stainless steel bench/bed/table in the big house?  taking the equipment and jailing the wackos will make a difference.  FCC is not funded at the necessary level to do that until the bands are happy and healthy.

just hope the babies stay in the crib...
58  eHam Forums / Misc / RE: Question - 600 Volts to 12 Volts? on: March 06, 2013, 10:31:54 AM
you can't find a wall wart for two bucks in a thrift store?
59  eHam Forums / Misc / RE: In the age of "virtual technical parity" Do Specs matter anymore? on: March 06, 2013, 10:29:26 AM
hasn't stopped the arguments among audiofools, and it won't here, either.

it all depends on what is good enough for you and your location.  if X works well and costs $3000 less than Y, is X good enough for you?

if it is really, really important that you have 140 dB rejection and the extra 0.004 uV sensitivity in a S4 noise location, hey, it's your money.  platinum edition Yugo, but have fun showing it off.
60  eHam Forums / Boat Anchors / RE: Swan 500cx tube mod ?? on: March 06, 2013, 10:23:33 AM
poking around the ARRL website yesterday, I found in the transceivers section of tech an article on replacing the ftdx101 6JE6s with 6146s.  pretty comprehensive.

that is NOT a Swine, however.  it should be a springboard to research of the schematics.  an item of interest is that a whole lot of functions between transmit and receive are shared in transceivers (duh!) and changing parts like tubes to others of different interelectrode capacitance can have effects far down the line in the other mode.

best mode is to find 6JE6s and run them lightly, don't pin the meters and dim the lights.  if you must convert to use the radio, read twice and highlight all the parts of the article that concern component replacement.  those areas... weak blocking caps, bias issues, compensating capacitors to make up for lost (or extra) tube Xc and make the finals tune again... are where you can have major problems.
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