T2 heating

[Andre Pollard]

Got the amp, LPF and TX board connected together last night, and tested into a dummy load. It all seems to be working well, except that T2 torrid is getting very hot. On longer tests I ran to check cooling ( a minute of CW key), T2 gets hot enough that you can't keep your finger on it for even a full second. Even on a minute of SSB, T2 gets quite warm. T1 doesn't seem to heat much, even on a minute of CW.

Here's what I checked:

1. SWR of dummy load. Nano VNA says 1.0xx, so it should not be reflecting power. It is made from 50 ohm microwave terminations.

2. Rechecked all components, solder bridges, etc. no issues I can see.

next is to hook up a arduino to the fwd and ref power outputs and track what it's saying. But I wanted to check here also.

Is T2 heating normal or an issue someone else has seen?

W4SFZ

Andre

[jcve...@gmail.com]

Hi Andre,

The Tc of the type 61 material is 300C. The PTFE wire is good to 327C and enameled wire is good to 250C. I would say that if you can keep you finger on it for 1/2 a second the temp is less than 70C so even if it's hot it's no where near where it might become an issue.

If it were 200C you finger would be burned on contact. 

73,

Jim WA2EUJ