Consentrating on Radio Amateur Electronics

[M0BSW]

Started to do some of the electronics and test gear in the shack today  , started with an important piece of gear. A 50  Ohm dummy load, for tuning up transmitters before connecting to main antenna's, this one is oil filled, using 20 x1Kx3watt metal oxide resistors, the oil I used this time is vegatable oil which is fine aslong as you remember to change it after 2 Years, otherwise it gores rancid, I change mine every year.
I thought of using DOT 5 mineral brake fluid, but I wasn't sure how it would react to RF.

[SeanB]

Better is to get some heated towel rail or oil heater oil and use that. Otherwise the cheapest 10w15 or other engine oil in the shop will work as well.

[M0BSW]

 I may well change it soon, I want to add a couple of signal diode to it so I can look at the signal out on the scope, for flat topping, and any spikes, so that be the best time to change it