Replacing the MiniTiouner

[aerostar]

There seem to be lots of hits via google

Here is one with prices

https://octopart.com/stv6120-stmicroele ... s-74146775

[PE5PVB]

What about splitting the RF and IF part. For IF you can use a SI2166. This chip needs IQ as input. The frontend can be a own design, so you won't be "locked" into the manufacturers limitations.

[G4GUO]

Like a lot of consumer oriented electronics, the biggest problem is sourcing the chips at low prices in small quantities.

The datv-express team have found that even when you do find an obliging chip company, you find a lot of them
are fabless and can only supply small quantities of their chips as prototypes because they use a 3rd party to make the chips so the
design company itself doesn't actually sell any chips.

The fab will only want to sell the chips in large quantities to OEMs.

[PE5PVB]

Don't know if you replied on my post, but the SI2166 can be bought for little money on Mouser.

[M0LNG]

The Si2166D is an interesting option. This is the demodulator chip used in the Octagon SF8008 receiver, where it reportedly works OK with RB symbol rates down to 100kS. In the SF8008, the Si2166 is paired with a RDA5815M tuner chip. The tuning range of that part limits the usefulness of the SF8008 receiver, but any other zero-IF frontend could be put in front of the Si2166D to get the required tuning range.

The main issue is the lack of documentation on the Si2166D, which is only available under NDA from Skyworks. However, there is the potential to reverse engineer the necessary register settings from the SF8008, which uses a Linux-based firmware. In this thread on the AMSAT-DL forum DL1JM was already successful in decompiling and patching the kernel module to remove some restrictions on the RDA5815M tuning range.

The Si2166D chips are readily available from multiple distributors and appear to still be in production.

[G4GUO]

Don't know if you replied on my post, but the SI2166 can be bought for little money on Mouser.

That is interesting, I believe someone at ORI obtained a Dev board for that chip a few years ago, but at that time it was
not easy to buy the actual chips.

- Charles

[G4GUO]

DL1JM was already successful in decompiling and patching the kernel module to remove some restrictions on the RDA5815M tuning range.

That RF tuner is the one used in the satellite side of the BATC Knucker, so we know how to program it. It is not the best of RF chips though (tunable range).

[PE5PVB]

Well, you can reverse engineer communication with this chip. Only issue can be if a microcode is uploaded to the chip at boot. This code could have copyrights.

Maybe BATC can get in touch with Skyworks and talk about possibilities. If a closed source driver is needed, it shouldn't be a problem. I think the same thing is done with the Knucker.

[G4GUO]

Maybe BATC can get in touch with Skyworks and talk about possibilities. If a closed source driver is needed, it shouldn't be a problem. I think the same thing is done with the Knucker.

For information

With the Knucker we used the manufacturer's reference implementation. The Linux kernel driver code was virtually identical to the manufacturers own code the only difference being the downloadable firmware, in Linux is a binary blob whereas the manufacturer's implementation it comes as C tables.

[PE5PVB]

Yes, but you need to make sure this microcode (wheter in C or not) is copyrighted.