Wednesday, 8 January 2020

Has it really been that long?

I had almost forgotten about my blog! I note that the last entry was back in August 2019.
An update on the IC9700 is required, together with my EME activities.

Having the IC9700 drift about on transmit and recovering on receive, especially when using digital modes on 23cm curtailed my EME activity.
I eventually bought one of the Leo Bodnar reference frequency injection boards as the VK1XX units were taking a bit too long to appear and the LB  boards were already  getting good reviews. Having to inject 49.152MHz rather than the 10MHz shack reference had previously put me off this approach. However, having a ‘spare’ dual output LB GPS source which would produce 49.152MHz, I decided to give it a go. Reliable reports had already shown that there was no impact on the transmitter composite noise over the existing, internal, reference TCXO. The new arrangement holds the IC9700 right on frequency, with no drift due to PA heating effects.

I am now back on 23cm EME and using JT65C with doppler tracking, I know where I am in frequency and can use the tracking to put my signal on top of the echoes from the other station, provided I know what frequency they are using for the transmit signal and their locator. I can easily see which stations are not using any form of frequency stabilisation, such as unmodified TS2000Xs and ‘stock’ IC9700 etc. by their drift characteristics.
This all makes EME operating so much more pleasant and reliable.

More anon

73 de Sam

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