Comments on: Scrounging an old DirecTV receiver

By: Cail

Cail — Thu, 29 Jan 2009 12:25:29 +0000

HI Barry,

I’m a poor man that has a broken VCR and could use a spectrum analyzer. Do you happen to have an URLs that have more details about using a commodity RF tuner as a spectrum analyzer? It sounds like an interesting project, and I’d like to learn more!

Thanks!

By: Barry

Barry — Thu, 29 Jan 2009 06:26:51 +0000

Another good item is the tuner module. Depending on the controlling I/O (analog, SPI, etc.), and RF/IF/Output characteristics (freq. range, IF, I/Q outputs, etc.) you can use this for a spectrum analyzer or a front end for a software defined radio. (SDR)

I’ve build a few “poor man’s” spectrum analyzers and have been working on an SDR using scavenged tuner modules. (from old VCR, satellite receiver and cable converters). The trick is to find the specs on these sometime proprietary parts.

Old C/Ku band satellite receivers are neat too. You can scavenge a lot of non-surface mount components / parts, particularly ones with a 70 Mhz IF.

Just a thought…

Barry (N5NWI)

By: Cail

Cail — Thu, 29 Jan 2009 01:34:03 +0000

I have a Emerging Display (http://www.edtc.com/) EW162C1YMY module that I scrounged a while back out of something (a network-centric PC-based computer appliance, IIRC). It looks to be a 2 x 16 block display (each block being 5 x 8 dots), and is soldered to a custom fab board that uses a PIC16LC65B to drive it. I’d be willing to trade all that (LCD, boards, and PIC16LC) for something, or guarantee it would be added to a TGIMBOEJ/scrounge box that headed my way. A partial data sheet (at least the pinout) seems to be here http://www.allelectronics.com/mas_assets/spec/LCD-97.pdf, but an inquiry to company (URL above) might also yield a better datasheet.

By: Berni

Berni — Wed, 28 Jan 2009 22:19:02 +0000

I would be interested in such a trade if i can get my hands on some useful data on how to interface the screen.Its no problem for me to make a pile of custom code for a MCU to interface it, but i want to see if i can even obtain a document describing the pinouts and interface. Since for some displays out there its nearly impossible to get it.

By: Shawn

Shawn — Wed, 28 Jan 2009 14:24:10 +0000

I do the same. I was given a bunch of DVR’s and modems from my work that we are taking parts out of. I was thinking about putting a section on our blog to trade parts. That way if someone is interested in parts we have we can swap.

I have a nice Sharp LM5H40TA LCD screen, pretty large, that came out of a Rocket eBook reader. Has the 20 pin ribbon on it. I am not sure how to work it just yet. I thought about trading that off if I could for a 4×20 LCD that I can use with ModernDevice’s LCD board.

By: dfowler

dfowler — Wed, 28 Jan 2009 00:22:44 +0000

@Cail… Yes there are some other interesting parts but they were surface mount and would be hard to reuse. I did not bother to look them all up to see if any were generic. Maybe I could do a high res scan and put that up for people to look at. If there were some neat parts you would be able to see them that way.

By: dfowler

dfowler — Wed, 28 Jan 2009 00:20:55 +0000

@Steve… On of my problems is that I just cant throw away a gadget till I get any parts that might be usable. I have to take a break and gut one of these now and then so I can walk though my workshop.. I agree with Cail, more stuff for a TGIMBOEJ.

By: dfowler

dfowler — Wed, 28 Jan 2009 00:18:07 +0000

@Berni… I agree, if it can be used as it, it should be. In this case the supply is well labeled and easily reusable. I just have too many of these from past scrounging. What I did not have was a good supply of power transistors and power resistors.

By: Cail

Cail — Tue, 27 Jan 2009 14:13:55 +0000

Per @Steve’s comment, what about creating a “great Internet box of old and scrounged stock”? This way we can cycle some of the old scrounged parts collecting dust off our shelves, and replace them with some new parts to collect dust.

@David, I noticed a couple things in the original picture that you didn’t seem to scrounge. Are those RF channel modulators at the front of the mainboard? I also see a PLCC flash. I’m sure the QFPs are probably specialized and not worth it (plus they are a PITA to hand solder), but there seems to be a fair amount of SOIC/SO/SOPs…anything generic and reusable? I also see at least four crystals.

By: Steve Chamberlin

Steve Chamberlin — Tue, 27 Jan 2009 04:49:17 +0000

I find I harvest all kinds of cool-looking parts that I’m sure I’ll find some use for, but then never do. Then they sit on a shelf for a year or two before I throw them out. Even though I’ve got a stock of hundreds of different components by now, the one I need for my current project never seems to be among them!