[Elecraft] 50 Ohm Load - source?

[Johnny Siu]

Very well said, don.
If ham does not need a new dummy load, there are a lot nice ones available in the used market at a very reasonable price.
Nowadays, frequency counter, RF watt meter and DMM are all available at a much affordable price.  Even a temperature controlled soldering iron is not expensive.  All those items were totally out of the question when I started my hobby at the age of 12.
Let us enjoy our hobby in a much affordable way now.
73
Johnny VR2XMC
       寄件人︰ Don Wilhelm <w3fpr at embarqmail.com>
 收件人︰ elecraft at mailman.qth.net 
 傳送日期︰ 2015年03月31日 (週二) 12:06 PM
 主題︰ Re: [Elecraft] 50 Ohm Load - source?
   
I think that attitude spells the difference between "appliance 
operators" and those who are willing to check out, and otherwise examine 
their ham gear.  How many "transceiver" problems turn out to be problems 
with the antenna system?  The number is larger than many are willing to 
admit.

In the long past, every ham had at least a few test tools - dummy load 
(even if it was a light bulb), and means of measuring RF and SWR (even 
if it was a pair of #47 lightbulbs on a piece of 300 ohm twinlead) - and 
that gear was used to determine if the transmitter was capable of 
producing power and if the antenna system was capable of accepting the 
RF power.

There were times when precise and accurate measurement gear was outside 
the budget of most hams, so we used substitute methods that gave us some 
indication that our transmitters and antennas were performing OK.

Today, reasonably good dummy loads and wattmeters are well within the 
budget of the typical ham.  When we are willing to spend $1000 or more 
on a transceiver, I find it foolish economy to decline to spend $100 for 
a few pieces of test gear to assure ourselves that that $1000+ 
transceiver is running properly.  It seems some hams would rather 'send 
it back to the factory for a checkout' than to make some simple 
measurements in the shack - the cost of that trip to the factory will 
exceed the cost of the equipment required to do simple testing of the 
equipment in place.

It does seem like false 'economy' to me, but I know there are some who 
will do just that.
And - when the transceiver returns with "no trouble found" because the 
problem was actually in the antenna system, that is not helpful.  The 
cause of the problem could have been identified if a dummy load and a 
wattmeter had been available and willing to be used for some simple 
tests.  The precision of the dummy load and wattmeter need not be 
extreme for tests of this sort - even gear with a 20% or greater error 
can give clues to the cause of failure in cases like that.

Yes, I now have precision dummy loads and wattmeters whose calibration 
is NIST tracable, but I use those for precision measurements.  To do a 
'sanity check' of where the problem may be does not require anything 
near that precision or accuracy.

As I have stated in the past, every hamshack should have a dummy load 
capable of handling the maximum output of that station.  It need not be 
exactly 50 ohms non-reactive (unless it is being used for calibration), 
but it should be a part of the diagnostic tools available in every hamshack.

73,
Don W3FPR

On 3/30/2015 5:43 PM, Dave Baxter wrote:
> I often wonder about people who will buy expensive (but excellent) radio's,
> then baulk at spending a few bucks, quid's or ?, on basic test kit like a
> half decent dummy load!
>
> Am I missing something?
>
>

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