[Central-Electronics] Another 200V back to life

[Peter Markavage]

As Colin pointed out, the jumper should have worked if on the correct
pins. My fan was noisy; no amount of clean and lube corrected the problem
so I replaced it with a DC muffin-type fan I found at a flea market for a
$1. I rigged some brackets to hold it in place. If you're going to
service the tuning hardware, make sure you place a tray under the
mechanism when you pull the shaft with all the bearings. The first time I
did one, I had bearings rolling all over the workbench at the same time.
I always use a scope on the RF output to monitor my modulated waveform. I
generally ignore blinking neon lights and meter movements for this
function. My mike of choice for the CE is a Heil Gold Line. The D-104
works fine when I want to punch through the QRM in a contest; the Shure
triple 4 sounds like I was talking through a metal pail. Got rid of that
thing years ago. I use my CE for both AM and SSB.

Pete, wa2cwa
http://www.manualman.com


On Thu, 17 Apr 2008 06:42:08 -0700 "k7fm" <k7fm at teleport.com> writes:
> My opinion:
> 
> "I am using a Shure 444 mic, would the Astatic D104 be a better 
> choice for 
> this xmtr?"
> 
> Depends upon your voice.  Try each one and take a vote.  Remember 
> this is a 
> democracy.  However, if 99% of the people say one mike is better and 
> 1% like 
> the other mike, you can select the one that 1% like.  Remember, you 
> are king 
> in the radio room.
> 
> "I removed the audio limiter and replaced it with the jumper as 
> suggested by 
> some; However, could not get any output so I re-installed the 
> limiter and it 
> works fine.  Bob said that I was one of the lucky ones that have a 
> limiter 
> that works. I still wonder though as to why the jumper did not 
> work."
> 
> The jumper was on the wrong pins, and did not jump.  Stood on the 
> ledge and 
> promised to jump, but did not and disappointed the crowd.
> 
> "I had lubricated the fan but it still seems quite noisy, is this 
> normal and 
> if not has anyone had any luck finding a replacement fan that fits 
> in the 
> space as designed."
> 
> I found a replacement from a scrapped Tektronix oscilloscope.  Build 
> a new 
> bracket and a muffin fan will work fine, though have a different 
> appearance.
> 
> "I am still having fine tuning dial problems but will address that 
> at a 
> later time."
> 
> You may need to service the bearings and clean and lube.  Nick Tusa 
> has info 
> on how to do this.
> 
> "Also, has anyone come up with a way to actually meter the speech 
> level 
> without having to interpret the light?"
> 
> Meters are very poor at metering speech, because their reaction time 
> is too 
> slow.  A neon light is excellent - you just have to follow the book. 
>  Also, 
> an oscilloscope is excellent to monitor the waveform.  Inexpensive 
> surplus 
> scopes are available for almost nothing.
> 
> Good job on getting the 200V back on the air.
> 
> 73,  Colin  K7FM
> 
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