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Attention: RC-CAM.com will be closing down August 2021.

The RC-Cam.com forum was the very first online community dedicated to the advancement of wireless video cameras on radio controlled (R/C) models. This is now called "FPV" (First Person View). We are proud of the contributions that our members have made to the FPV hobby.

We've seen significant changes over the last twenty years. Initially there were a lot of eager R/C hobbyist that built their own video systems. Allowing these creative individuals to share their work was the purpose of this site. Now the FPV market is flooded with low cost systems; Sadly DiY FPV video projects are now rarely discussed.

RC-CAM.com (main site and forum) will be closing down August 2021. This is being announced now (March 2021) so that everyone has time to download any information that is important to them. After the site is shutdown the information will no longer be available here.

We appreciate every member's involvement with advancing the FPV hobby. It is indeed sad to say goodbye to all our online friends. Be safe and stay healthy.



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I've read about gaining 3dB or so from doing the saw filter mod.

I think I understood that the reduced bandwidth gives better reception qualities to the receiver.

IIRC people were switching to the ECS-D480A saw filter which has at 3dB a pass bandwidth

of only 17.6MHz and comes with the usual insertion loss of 19-20dB.

BUT

I was wondering whether the gain for the receiver could much bigger when using a [b]low insertion loss saw filter like the VANLONG SF480 which has a rather normal 22dB bandwidth but comes with only 2.5dB insertion loss! :)

Wouldn't that mean the signal is not dampened by the usual 25-18dB insertion loss but only by 2.5dB,

hence "attenuating" the signal by 15dB or more! :D :D

I'm bad at rf technology, and don't know whether subtracting the dB numbers is correct but I don't understand why only the 480MHz saw filters have such a high insertion loss, check out that VanLong SAW Filter table, third column.

Only "our frequency" of 480MHz saw filters have that 20dB insertion loss, except for the SF480 (w/o any dashes).

Any satellite rf tech willing to clarify?

I'm trying to get that SF450 2.5dB il to mod one of my 12 channel receivers to test that.

Seems this eurpean VanLong distributor is rather uhm slow at responding to mails.

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Unfortunately the SF480 is a RF filter, not a IF filter. Both are used in a receiver's design, but they are not for the same purpose. The reason the IF filters have the higher insertion attenuation is due to their needed precision.

Perhaps it would be interesting to see if the RF filter could be used in the IF location, but I don't expect it would be a drop in swap. So be sure to report back your test results.

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