I started to order parts for the CNSIP project. But the part for the mixer (X1) BF1105R,215 (SOT-143R) is not available. Does anyone know a good replacement for this N-channel dual-gate MOS-FET ?
I’m new on this forum.
Hi, regarding that dual gate (mixer) transistor, as it stands I doubt you will find an equivalent still in production. Unfortunately this is the issue that keeps perpetuating with quite a few of the past Patreon (published) projects. I see 2 potential solutions to you current dilemma. 1. you can try to send MCL himself a message (via the Patreon route) and…who knows….if you are lucky he might come up with some suggestions or tell you how to modify the project so some current production part could potentially be used then. or 2. Bite the bullet and try to source the part via some other sites IE: eBay, Amazon or, some shady Chinese sites etc etc. Otherwise it is clear that you will basically be stuck and unable to succeed with the project. I was lucky that I’ve built the project when was first published on Patreon (back then) and the part was widely available everywhere and have purchased 10 of those to keep as spares (just in case). Good luck.
There’s a comment the 3SK293(TE85L,F) is a substitute albeit the pinout is different & the voltage spec is reduced. It is also classified as Obsolete however some suppliers have the last few instock so you may be able to complete your project. I never saw the CNCSIP project when it came out so having just now watched the video series I have obviously missed a great opportunity to make a very useful test instrument that would be so good with what i am doing now that i am retired!
Aliexpress have it. I know its a risk from China . I have ordered lots of semiconductors from there and not had any bad ones
