Well, the title says it all: I want to start making EME contacts with the lowest possible budget, and I doubt between 2m, 70cm and 23cm. Since I cannot afford those expensive power amplifiers for these frequencies, I decided to go for a big yagi array instead (increase the gain of the antenna in order to get an equivalent EIRP compared to the PA). I have a lot of experience in antennae design and simulation software, so this won't be an issue.
These are the options I have:
2m: I have a 50W TX, and could afford a cheap 100W VHF amplifier such as this one. For the antennae, I would build an array of four 6-element yagis. Each yagi should have a gain of around 9,7dBi, so the whole array should provide around 15,5dBi.
70cm: My rig is able to provide 35W at this frequency. However, I did not find any affordable amplifier for this frequency. For the antenna, I could use some four yagi array, that would provide an overall gain of around 16dBi.
23cm: Due to the smaller wavelength, I could try some 6 or even 9 yagi array. They would be around 12 element arrays and provide a global gain of 18,5dBi. Nevertheless, my rig (ICOM IC-7100) does not work at this frequency, so I would need some kind of upconverter. I did not find any cheap solution that works at the desired power outputs (around 50/100W).
This analysis suggests me that I should go for the 2m option. Moreover, path loss is smaller at 2m than at 70cm or 23cm. However, all of the beginner/small EME station work on either 70cm or 23cm. Moreover, I fear choosing a frequency that is not being used too much, and making few contacts because of this.
Any advice or recommendation will be appreciated.
BTW: for working EME, is there any noticeable difference between building an array of 2x2 or of 4x1 yagi antennae?
73 de EA4HFV!