Hmmm, understand what you are saying / where your coming from etc and it did seem to optomise using the conventional design scalar as used on the previous Precision 2.2 . I'll have a more serious look at it when the weather is a bit more friendly towards outside work.
Apologies, a bit late in replying, I have not worked with the Cband models for years but the same should apply at all frequencies.
The earliest Precision feeds for Ku band do not have a scalar ring as such, but a single 'lip' that is formed from the metal part used for affixing the three feedarms.
There was a second version produced a few years later which increased the number of surrounding rings to three and this coincided with a different design of the 90cm reflector that was decidedly thinner and did not have the fully rounded edge.
I did install three 90 cm versions on the Gorizont satellite at 14 (or was it 11 ?)West for client wishing to receive the state Russian channel in SECAM back in the very late 80's and tests confirmed at the shop that hand-holding the Cband LNB at the dish without the scalar ring included in the kit would reduce the sparklies, but I did not have a method to secure it in place without making something bespoke.
This was put down to the additional gain owing to less shadowing but I was never truly convinced because of the Ku band feed designs offered at the time.
I will try to find an old catalogue showing what Precision supplied for use at Cband but I would hazard a guess their reflectors were designed with a surface accuracy that means the improvements of signal collection using a scalar are not necessary.
