Laurie Mayhead wrote:

In a recent mail Mal said that he was not surprised that my sigs were heard/seen in Canada, and that all that is required is a high/ long Ant and 1-5W ERP. This is quite true but I should like to point out that my Ant. is only 48ft high,although the top load is 600ft. Also my power was only 125mW. I agree that  more could be done with a bit more power and a higher Ant! but thats no reason for not trying Unfortunately I don't have a TX at the moment after my Bar-B-Que,but there must be others who do.73s Laurie.
Sorry Laurie to hear about your misfortune just in the middle of of your experiments, perhaps it got over EXCITED !!!!!!!!!!!!!!!
I use the same tx for both 73 and 136 khz, just change the drive input frequency and a different LPF at the output for each band. The tx is similar to the YXM design and runs nearly 1kw output.
The tx is robust, no explosions to date hi, but I monitor the SWR and DC current carefully for any changes. My antenna is also robust, with good quality insulators and 2.5 mm insulated wire through out. The system is all matched to 50 ohms, and every precaution taken to avoid any variations in loading. I observe virtually no changes regardless of the WX  except in gales when there is movement of the antenna wires, even then the swr does not exceed 1.5-1 but if it went higher I would close down until the storm passed. Precautions like the above avoid MELT DOWN !!!!!!!!!!!!!
My ground system consists of 2.5mm insulated radials and some sheep fencing (no buried copper wire)
73 de Mal/G3KEV