Two metre wspr

This summer I have been trying to get some activity on the two metre band. In the past I have not observed much activity in New Zealand but recently ZL2IT and ZL3PX have been on regularly, and exchanging reports. I have recently joined in, and another wsprer I have seen is ZL2COM. These station seperated by long distances, the shortest path I think is from ZL2COM to myself about 200 km.

My set up here is solar/ battery powered with any 230volt needed coming from a 12volt pure sine wave inverter. This is used to power a 20amp 13.8 volt stabilized supply. The two metre rig is a Kenwood TR9000 all mode transceiver, which I bought new in about 1978!
Yes almost an antique and limited to10 watts out. The antenna is a home brew 6 over 6 yagi array mounted on my alloy pole GP antenna support.
The old TR9000 is performing okay except for me having some problems geting the frequency readout accurate enough for wspr, and stability is an issue with the very warm temperatures in my outside of the house shack (yes it is a shack). This temp can vary in the summer from 18C to 38C which puts the TR9000 under extreme pressure. In fact to keep it anything like stable I had to remove the top cover and install a fan on the heatsink at the rear and another on top of the PLL and carrier oscillator units. This appears to have done the trick and receiver drift appears to be acceptable as per the original specs accoding to the manual, and the drift on full power transmitter (10 watts) is limited to 4 hz, which works. Not bad for a 40 year old design.
Another problem is long periods of operation are exceeding the capability of the power generating capacity. I may need to get another battery! Or dump the ACER lap top for something more economical with my precious solar power.