It’s been on my mind to make this post for quite a while now. Some time back, a very generous ham in Oregon gave me a sizeable quantity of SA602 and SA604 SMT IC’s. They were part of a production run that didn’t materialize. He got a deal on them and has been hanging onto them ever since. Now he would like to pass them on (for free) to other home-brewers, so he asked me to help out. He wants them to go into the parts bins of people who may well use them, and does not want them to go to people who will merely resell them for a profit. He’s perfectly OK with them being used for a club group build, or a club kit designed to raise funds for a QRP club – just not in large quantities to individuals who will turn around and sell them. The idea is to encourage people to build something.
I’m sure you know all about the NE602/SA602/NE612/SA612 oscillator and double-balanced mixer IC. It has, of course, been used in countless numbers of simple direct conversion receivers such as The Sudden. It’s not ideal in the front end of a receiver, being very susceptible to overload in that usage, but it sure does make it easy to build a very simple DC receiver. It can be used to good effect as the 2nd mixer in a receiver, and as a balanced modulator. In any application where the input levels are within certain defined limits, it performs well. The SA604 is a low-power FM IF chip. I’ll leave you to do the research and check out the datasheets.
Oh – and these IC’s have been through rigorous quality control. Here’s Sprat The QRP Cat checking the roll of SA602’s. They passed the test 🙂
The SA602’s are in an SOIC-8 package and the SA604’s in an SOIC-16 package. Here is one of each, placed on a sheet of W1REX’s MePADS –
Jason NT7S built a really neat SSB rig based around an Si5351 PLL/VCXO chip. He used 2 of these SA602’s as part of the design. you can read about (and see) Jason’s “Simple SSB” rig here. He describes the rig’s architecture in an earlier post here. It’s great stuff and very much in the spirit of ham radio.
I don’t want to make any money from this, but would like to cover my expenses, so I will charge a small fee to cover the cost of a padded mailer, postage and the Paypal fee. Here’s the deal. If you are an individual home-brewer in the continental US who could use some of these SA602 SMT IC’s (which are exactly the same as NE602’s), send me an e-mail – either to my e-mail address on QRZ, or to firstname.lastname@example.org to let me know you’re interested. I’ll reply to let you know what e-mail address to Paypal the money to. For $4, I’ll send you 15 SA602 IC’s. If you’d like some SA604’s as well, let me know but please only ask if you think there’s a chance you might use them. If you would like a larger quantity for a club kit or group build, send me an e-mail with the info and I should be able to help you out.
Oh – and unlike my recent variable capacitor give-away, I have quite a lot of these, so you don’t need to be the first (or even the 20th or 30th) person to reply. As not too many builders use SMT, I suspect this offer will be available for a while.
I am very grateful to the gentleman in rural eastern Oregon who is the reason for me to be able to spread this little piece of home-brew goodwill!
NOTE – to the gentlemen who left comments, I have deleted them. It occurred to me that having your e-mail addresses and info in the comments section might cause some enterprising scammer to pretend he/she was me and ask you to send the money to them. Having said that, they would have to be pretty desperate to go to all that trouble to make an extra $4! Best to e-mail me at my e-mail address on QRZ, or to email@example.com
NOTE – SA602 and 604 offer on hold until further notice. I’m almost out but the very kind gentleman from Oregon who sent me this batch has some more he will be sending soon. I will make a new post to this blog when I have more IC’s in stock.