[time-nuts] Mercury Ion Clock

EWKehren at aol.com EWKehren at aol.com
Mon Nov 3 07:58:43 EST 2014


Do not want to get off list subject but again have to disagree. First I was 
 not referring to $ 2500 spectrum analyzer but a single frequency source. 
As to  equipment available some of the equipment on ebay is not visible to 
offshore  buyers. It also helps to know your sellers and I am not talking  
actually have talked to them but understand their listing. Just checked my buys 
 and on July 1st 2012 I bought a Wiltron 6740B 40 GHz excellent condition  
for $332 total cost. You could not have bid on it.
All I am saying that 40.5 GHz should not be hindrance to pursue Mercury Ion 
 there may be more challenging issues and if time nuts want to do something 
I may  be able to furnish that source. Like I said before I commit I would 
have to  better understand the requirements. 
Bert Kehren
 
 
In a message dated 11/3/2014 5:09:08 A.M. Eastern Standard Time,  
drkirkby at kirkbymicrowave.co.uk writes:


On 3 Nov 2014 02:59, "Bert Kehren via time-nuts" <_time-nuts at febo.com_ 
(mailto:time-nuts at febo.com) >  wrote:
>
> I respectfully disagree. Before getting totally  submerged in time nuts
> issues I did extensive work on signal sources  up to 40 GHz as a hobby. 
So I
> have  since the early 90's sweeper,  synthesizer, power meter, mixer for 
the HP
> 70000  series,  attenuates and most important frequency counter and non 
fall
> off  the  cliff at 40 GHz. 40.5 is still doable the limiting factor is  
wave
> guide cut off  frequency. One of the reasons I still hold on  to the 5345
> frequency counter the  best for high resolution  frequency counting in 
that
> range. Yes it was not cheap  but more  and more equipment and components 
become
> available last year I helped  a  friend sell eight HP mixers for 
frequencies
> above 50  GHz.
> The big question is phase noise and how much power and no it will  not be 
$
> 200 but $ 2500 depending on power and phase _noise.is_ (http://noise.is/) 
  attainable.
> Bert Kehren 
I doubt that you could assemble either a spectrum analyzer or  signal 
generator at just over 40 GHz for $2500. A frequency counter one could  easily 
do. 
I puchased a used 20 GHz sweeper in the UK last week for the US  equivalent 
of $900. I think that was particularly cheap and probably helped by  the 
fact that the seller had poor feedback and didn't do a good job of  describing 
it. But that was "only" at 20 GHz. 
A US dealer, who is kindly going to give me a software code to  enable a 
step size of 1 Hz, rather than 1 kHz said it was worth more than that  in just 
parts.  
Waveguide modes should not be a problem if you use either the right  size 
coax or waveguide.  In coax that means using 2.4 mm  connectors,  as both SMA 
and 3.5 mm can't work at 40 GHz. But anything in  2.4 mm is going to be 
expensive. A simple female-female adapter is like to  cost nearly $100. 
I just looked quickly on eBay and could not see any working 40 GHz  signal 
or sweep generator for less than $15,000.  Neither could I find a  non 
working 40 GHz signal or sweep generator for $2500. As I wrote  earlier,  40 GHz 
tends to be one of the frequencies that commercial gear  stops at, so 
getting to 41 GHz is likely to be substantially more expensive  than 40 GHz. 
There's now quite a bit of modestly Chinese test equipment up to a  few 
GHz, but I don't see anything modestly priced at 40 GHz. So I don't think  
$2500 is likely to buy you a lab of 40 GHz test equipment.  
I am sure if one waits enough,  one will find a cheaper unit  on eBay,  but 
I think that one is still going to be paying serious  amounts of money.  
Dave


More information about the time-nuts mailing list