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Good dummyload


KE5MC

Guest
Feb 8, 2009
134
6
28
Grapevine, TX
Good for me

Diamond DL30A

Fits my needs and expectation. I think MFJ makes one that looks like it. Air cooled with fins, pocket sized.

Not clear in most on-line adds what the power handling is. From the included Japanese/English insert.

15W Continuous
20W 5min. on/ 5min. off
50W 1min. on/ 3min. off
100W 30sec. on/ 5min. off

50ohms

VSWR 1.15(DC-500MHz)

Connector PL-259

Dimensions: 30mm dia x L75mm

What do some of you use?
 

Captain Kilowatt

Professional Amateur
Staff member
Apr 6, 2005
16,880
11,088
823
59
Nova Scotia,Canada
For lower power stuff I use the MFJ-264. Don't believe the rating you see. that is only for about half a minute or less from a cold start. It will handle 100 watts continuous.

DUMMY+MFJ264.JPG



For more demanding situations I use my homebrew load made from ten 500 ohm, 200 watt watt Globar resistors all mounted in a 12 quart stock pot and filled with silicone load oil. I must admit it is pretty sad when your tubes don't have handles but your dummy load does. :headbang This load is good for 2000 watts in air and God knows how much in the load oil. I figure it's good for 10Kw at least. It has had 4 Kw peak into it for 15 minutes straight and was only just beginning to get quite warm near the top.


dummyloadyt4.jpg



underthelidvv9.jpg



finishedloadnp8.jpg
 

flush

Member
Mar 16, 2008
27
1
11
50th State
This is my big one. I called to get info on this one and they said it could do a lot more than the 600 for shorter times. 600cw all day.....

2011-08-12162638.jpg
 

CroMagnum

Member
Dec 6, 2010
80
2
18
I use one of these I found on eBay:

sf7y1k.jpg


I modified mine by swapping the N-connector for an SO-239 and added some little rubber feet. 250 Watts continuous in free air for $30 delivered is not too bad.
 

GnG8d

Well-Known Member
Jun 28, 2010
2,037
344
93
Ohio
Would like something capible of 1000 watt avg 3000 pep

Take 2 MFJ264 loads and use a 75ohm cophase harness to run them in parallel. Or, just buy 4 of the resistors only from MFJ and run the 4 in series-parallel submerged in transformer oil, that ought to be good for close to 10kw and cost less then $300 or so.
 

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