On Wed, 12 Dec 2012 17:23:35 -0800 (PST), Dana wrote:

On Saturday, December 8, 2012 6:31:35 PM UTC-8, Arid ace wrote:

With so many data sheet archives online, I could have hit the wrong one.

Since the TL026 is a currently-produced part by TI, there's no need to
sift through online archives. Just go to http://www.ti.com/ and look
up the part number.

What remains is the large current consumption - typ. 22 mA.
For the SL612 the typ. value is 3.5 mA.


But what didn't fail to get my attention was the remark "Other
Characteristics Similar to NE592 and uA733".

Fair enough. Of course, the TL026 *isn't* either of those parts,
and the statement suggests to me that the TL026 has input and output
characteristics similar to those non-AGC parts - relatively easy to use.
Nothing at all about internal architecture. Perhaps you're reading
something that isn't in the datasheet at all. Given how cheap the TL026
is, perhaps you might try one instead of an SL612 and see if your
assumption is true.

Cost is a nonissue as is production. Another 30 mA just for the IF amplifier of
a noise blanker is an issue though.

But, seriously, you're quite passionate about the SL612 and
that's a wonderful thing.

Cheers,
Dana K6JQ

No, for the noise blanker it's the best solution. The IF minus impulse noise
will be processed by another no longer available IC, the TCA440. Its mixer and
IF combined have an AGC range of ~100 dB with max input to the mixer, 500 mV
rms, current consumption ~11mA. With the 30 dB AGC range of the 2nd mixer, 120
dB AGC range. That mixer will convert to 25 KHz, a nice value for razor-sharp
notch filters and ideally working (synchronous) demodulators. Why be satisfied
with less when it's so easy to design a radio that functions well with input
signals between 0.1 uV and 100 mV and yet has a low power consumption? ;-)

Jan