Old EME dish in JN68rl, QRV 1987-2016, dismantled 2019

Three big wind storms (1990, 1999 and 2007) nearly damaged the large dish. Although it could be repaired every time, the parabolic shape of the reflector had suffered step by step. For example, I found out by sun noise measurements, that the performance on 23cm was only as good as a perfect 6m dish at the end, even on 70cm degradation was noticable.

Last QSOs on 70cm and 23cm were made in 2010.

On 2m last QSOs were made in 2016.

2019 I noticed that welded joints in the elevation systems had broken. As repairs were not possible, I decided to put down the dish after 32 years.

Here you can find some audio samples and signal plots I made long time ago with the big dish.

ANTENNA: 11.2m dish, homebuilt f/D = 0.41 2m & 70cm : Dual - Dipole - Feed 23cm : W2IMU - feedhorn
Because of feed interaction, the effective diameter on 70cm is 10 meters only. On 23cm the efficiency is even less because of underillumination. The gain on this band is equivalent to an optimized 9 meter dish.
Usually I could hear echos on 23cm with as little as 1 Watt at the feed !	Preamps.: 2m : MGF1801 70cm: FHX35 + MGF1302 23cm: FHX35 + FHX35	Power amplifiers : YL1050 on all three bands Drivers: 1x2C39 on 2m, 2x2C39 on 70&23cm 3 - phase power supply

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