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Something efficient and has very low losses. Joe WB9SBD

AWG 36 with a green PTFE coating and a full 241 feet long .

Wondering what kind of antenna is used that will handle this much power? A

I designed this amp (back in 2007) for a buddy, who is now SK. Current owner is in MT. It uses a custom 253 lb Dahl plate xfmr and 24 x 3900uf lytics. Vac relays used for the input + cut off bias.

60/50 = 1.2 SWR of 1.2:1? is good enough. Typ with DL resistors..... once u cook em a few times, they will drift a few ohms up in value.

My Bird 5Kw reads 50r + - 2 ohms through 900mhz , but I wouldn't hesitate to feed my 30S-1 into a 60 ohm load. Don W4DNR

If you use them (or it) for a dummy load, they (or it) will require a large heat sink. 73?? Bill K3HZP

Gents, Looking at resistive DL's for QRO is an interesting pursuit, and the recommendation about employing a VNA makes it a good return on investment when selecting the "bits." One of my DL's is a

It would take the op all of 30 secs to parallel the 2 x 100 ohm resistors and see if they are inductive.? ?Heck only 1 is required for this test.

Thanks for all the replies. I don't need a dummy load, I just have this stuff laying around. I'll probably just try for the heck of it. Again, thanks for the replies.

Hi – I would say giver it a try. Put it together and then use a network or antenna analyzer and check the DL for return loss. 73 – Mike Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731

Scott, I may be reading too much into this, but when people post to a group named "ham-amplifiers" and mention "a couple 1KW ... resistors" I can only assume that they plan to homebrew an HF dummy

Mite want to check the SWR of it or a scan with a VNA or some such to see how it looks. A -- "Where the Old Soo crossed the New Soo" Duplainville, Wisconsin Web page: Http:/www.dupyrail.com Youtube

Reminds me, I built a dummy load with twenty half watt 1000 ohm resistors in parallel between two coax braids dunked in a gallon of ND30 motor oil in a one gallon pain can. I haven't killed it yet

You can always take two of the 50 ohm resistors in series, paralleled with another two 50 ohm resistors in series. Should give you 400 watts of dissipation. I'm using 2 paralleled strings of 4-100 ohm

John, Does the datasheet for that "planar resistor" say it's non-inductive? If not, then it probably won't work as a dummy load, except at audio. ebay has some 50 ohm non-inductive resistors but

I'm wondering if a Planar resistor can be used for an RF dummy load. I have a couple 1KW 100 ohm Planar resistors and an 18# heat sink, I can't find my answer anywhere. Any information will be greatly

Jim, that sound about right. Years ago I ran a Ranger and a Thunderbolt amp. This combo is very inefficient. In AM mode they ran the pair of 4-400 with 350 MA if idle current. Then, they had your

Just curious, the feed through power of a G-G Amp might be ~ 2 to 5% of the power output when the tube has a high Mu. For a low Mu tube, that could be upwards of 20%. The self modulated control grid

The tube hi-pot tests 30 kv (anode to grid)...and? 5 kv (grid to cathode).? This is normal for a 3x10.