Tuning up with Dummy Load

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Ronald A Houle:
   I have a Kenwood TS-50 Transceiver.  I tune up by switching to FM on low power and adjust my antenna tuner for min SWR.  When you transmit into a dummy load you can read the max forward power and this TS-50 does not allow for adjustment for max forward power.  
  I also have a Kenwood TS-520S and I find that the dummy load is effective in adjusting the load, plate and drive controls for max forward power and then switching over to antenna I find the SWR pretty good.
 Other than using a dummy load on a modern transceiver to check forward power it does not seem to have as much application in modern transceivers as it does in the older vintage radio's.  Am I missing something here?  

Alan Applegate:
You're going to get several opinions here, that's for sure.

Every radio and amplifier I own is solid state. I still own a dummy load, as should every other amateur with a license. For example, there are numerous posts here on eham.net dealing with "tuners" and antennas that have too high an SWR. The best way to fix problems like this, is to lower the variables to a minimum (radio, wattmeter, dummy load, and known good jumpers). Then slowly add the components to the problem pops up. This is just one use.

When I work on a radio, I never put it on the air, especially into an antenna that has reactance. Doing so negates what little accuracy most wattmeters have.

As for the older rigs, when used with a tuner, it is always best to tune into the load, and adjust the tuner next. You should also log the settings so the next time your tune up takes seconds, not minutes like you hear quite often nowadays.

There are a lot of other good uses too.

Alan, KØBG

Steve Katz:
A dummy load is a useful accessory; however if you have nothing to "tune," and use a solid-state rig to simply connect to an antenna and make contacts, that application doesn't dictate the use of a dummy load, at all.

Even with a "no tune" solid-state rig, a dummy load is useful for setting up transmitter parameters, checking power output, setting mike gain/speech processor adjustments, setting CW keyer speed and lots of stuff you might want to do without putting a signal on the air that others can hear.

I can go weeks without ever using a dummy load (and meanwhile making hundreds of contacts on the air), but then find myself using one a dozen times in one weekend for various reasons.


Dee D. Flint:
I use my dummy load to check all kinds of things on my solid state transceivers as previously mentioned by others.  I particularly like to use them when setting mic gain and setting up the speech processor.

On the TS-50 (and other radios), I use the CW mode (if available) to tune my radio.  If you ever purchase an automatic antenna tuner for the radio, the radio will automatically use the CW mode when you press tune.

While using a dummy load allows you to do these checks "without putting a signal on the air", there is a minute amount of energy going out over the airwaves.  So don't be surprised if someone answers you one day.  I had finished checking my radio and forgot to change the switch from the dummy load to the antenna.  Later in the day, I heard a faint signal and answered it.  We had a nice qso and signed off.  Then I noticed that I was transmitting into the dummy load not an antenna!

Taka Kamiya:
I see a hamshack as two pieces.  What's inside and what's outside.  When I sense something is not right, the first thing I do is to disconnect the antenna and replace it with a dummy load.  It's a really good way to start troubleshooting.

Although not as useful as the days where radios had tube finals, it is still a valuable and necessary component.  

Oh, yeah....  One time, I kept having problems even with a dummyload...  It ended up, my dummyload was defective.  (lock thread that held one end of the resister came lose)  Now, I have three....


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