On Tue, 29 Nov 2011 13:25:27 -0500, Eddy Swynar wrote:
>
>It's obvious that proponents of utilizing cooling fans for their Drake
>transmitters are on to something, alright---but the benefits are NOT
>restricted merely to prolonged tube life: PTO drift is reduced by one third,
>as well.
This,
Steve -
Sure sounds like bandswitch. Don't forget to check bandswitch hardware for wafer alignment, AND
check wafer center holes for oblong and not round holes!!
You DID disconnect the electrolytic caps from the old twist-lok when you tacked
in the tubulars?
Verify the RF TUNE pointer i
Absolutely - love reading these escapades! Since I author a few of them
myself, I happen to find those of others equally interesting.
73,
Steve Wedge, W1ES/4
I swear by my life, and my love of it, that I will never live for the sake
of another man, nor ask another man to live for mine.
-Ayn
I'll second that... it's epics like these that make this and other lists
worth riding along with.
Thanks for taking the time, and thanks for the info. I always knew fans
were a good idea :-)
John K5MO
At 01:47 PM 11/29/2011, Robert Fish wrote:
" This has all been a most interesting exercis
I have not taken out the scope or meter yet. Observations are somewhat random.
My friend Keith's T-4X spent who knows how many years in a New Hampshire
cellar. Keith got it at a hamfest long ago, from parts unknown. It was
obvious to me that it had belonged to a smoker and was pretty grungy a
" This has all been a most interesting exercise, nonetheless---I only
hope that my ramblings herein have NOT inspired readers to unsubscribe
from the list..! "
On the contrary, Eddy. I find this stuff fascinating. The most
productive learning environments always have people who say things like
Eddy -
Great info. Actually this confirms what I would expect to happen. What you do with the fan is
provide a constant temperature, whatever it is, much better for short-term stability.
The other oscillators involved in the output frequency are the Carrier Oscillator and the Band
Oscillato
Hi Again All,
At the specific suggestion of Garey, I went ahead & completed a 3rd stability
test on my Drake T-4X transmitter PTO...
I essentially repeated everything that I did in the very first test, i.e. I
used the ICOM 751A as an umpire, both it and the T-4X were started at the same
time (
Yes it is for output or input frequency. The other oscillator is crystal controlled, so not likely
to move even 10 Hz over this restricted range.
73, Garey - K4OAH
Glen Allen, VA
Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line
and TR-4/C Service Supplement CDs
Steve Wedge wrote:
Which brings us to
Which brings us to an interesting point: isn't the spec for the stability of the rig overall? I don't have the manual with me, so I'm just asking.
Steve, W1ES/4
PS - nice work, Eddy!
-Original Message- From: Eddy Swynar Sent: Nov 29, 2011 10:57 AM To: Curt Cc: drakelist@zerobeat.net Subj
Hi Curt,
A sort of an elaborate "...temperature-compensating-oscillator-heterodyning"
scheme...! Hi Hi
We could call it "The Rube Golberg" method of frequency stabilization!: >)
~73~ de Eddy VE3CUI - VE3XZ
Hi Garey,
An EXCELLENT idea...!
I'm doing exactly that, even as I type this...
Stay tuned!
~73~ de Eddy VE3CUI - VE3XZ
**
On 2011-11-29, at 9:26 AM, Garey Barrell wrote:
> Hi Eddy -
>
> Would you be up for one more t
Hi Eddy:
Excellent! Now, you might also learn something worthwhile by doing the
same test, but measuring the drift of actual output after mixing at say
7 or 14Mhz. If the crystal Osc goes the other direction, it might get
somewhat better...then again if it goes the other way...well...! :)
Hi Eddy -
Would you be up for one more test run??
I wonder what would happen WITHOUT the fan. Certainly the interior would warm up faster. A
trade-off would 'perhaps' be a larger delta t from transmit to receive. Especially without an
ambient air of 59F constantly being pulled through the c
Nice work Eddy.
I do my tests a little differently, I look at "overall" stability by zero
beating WWV.
Regardless, my early T-4X (5KHz markings) is also just about 1.2KHz.
But my slightly newer R-4A (13 tube, but 25KHz markings and vernier Preselector)
is worse at just about 1.5KHz.
IIRC, ther
Hi All,
Well, this morning I essentially duplicated my previous stability tests with
the Drake T-4X here, only with a minor change: as was suggested to me earlier,
this time I let the "umpire" rig---my ICOM 751A transceiver---warm-up, alone,
for a full hour...
Before getting to the results, I
16 matches
Mail list logo
