Need Help Locating IC for Scanner

[bby]

Just bought a Pro-26 that needed work. I am looking for a TC74HC4094AF. I think it is called a shift register. If anyone knows where I can find one, please let me know. I tried Radio Shack and the part has been discontinued. BTW, on the Shack's online parts book for this model it lists this part as being TC74HC4094AF (EL). Could someone please tell me what the (EL) is supposed to signify? Thanks

 

[K5MAR]

Checking on this scanner for you on the mods.dk website (check for the link in the Radio Shack Forum), this appears to be a Uniden-built model badged for Radio Shack. Try Uniden service, maybe they can help.

Mark S.

 

[bby]

I thought about that too, but figured since RS has dropped the item, probably Uniden had too. Also, just wondering how to get Uniden to check this (even though they made it) considering it is carrying a Realistic name. Also, since Uniden made it, does anyone know of a Uniden model that would be the same?

 

[EricCottrell]

Just bought a Pro-26 that needed work. I am looking for a TC74HC4094AF. I think it is called a shift register. If anyone knows where I can find one, please let me know. I tried Radio Shack and the part has been discontinued. BTW, on the Shack's online parts book for this model it lists this part as being TC74HC4094AF (EL). Could someone please tell me what the (EL) is supposed to signify? Thanks

Hello,

The 74HC series are High Speed CMOS that are pin-compatible with the 4000 Series CMOS devices. TC indicates it is made by Toshiba. You are looking for a 74HC4094A. The F indicates it is a SOP-16 package. Likely a regular 4094 will not be fast enough.

There is a link to the data sheet on this page.
http://www.semicon.toshiba.co.jp/eng/release/omc/list_osc_logic.html

You need to find a parts supplier that carries Toshiba or find out if Texas Instruments or another chip maker also makes the chip in the same package.
Likely you need to go to a on-line distributor like Mouser, or Newark.

A couple of places that may have the original Toshiba part.
http://www.sourceresearch.com/toshiba-america-semiconductors.cfm
http://www.4starelectronics.com/manufacturers/Toshiba_Semiconductors.html
I have not dealt with either of the above companies..

73 Eric

 

[bby]

Thanks Eric. I have been searching on google and came up with several results. The only problem that I have had with the results is that it is all in bulk. I only need 1 of these, and most of them are 100 or more. I found some sites who had a minimum order of $100 or more. I also found another one that ended in AP, but I have no idea what the P signifies or the (EL) that RS had beside of the component in their parts listing. Can you help me on any of these? I did take electronics class but that was 20 years ago. Needless to say, I didn't end up in that profession.

 

[VegasCorbin]

Thanks Eric. I have been searching on google and came up with several results. The only problem that I have had with the results is that it is all in bulk. I only need 1 of these, and most of them are 100 or more. I found some sites who had a minimum order of $100 or more. I also found another one that ended in AP, but I have no idea what the P signifies or the (EL) that RS had beside of the component in their parts listing. Can you help me on any of these? I did take electronics class but that was 20 years ago. Needless to say, I didn't end up in that profession.

Just an educated guess but the "P" most offen means it is in a plastic case rather than ceramic. This will affect the tempature rating of the device but not effect how it works.

Another source could be a compaany called Digi-Key. I have not used them directly but the company I work for has used them to order parts. They have been around quite a long time. Mouser is another company that my work has used.

This part at one time was very common. Most electronics supply houses will have them in stock. Here in Vegas if I needed one I would go to a place called Sandy's Electronics. It is part of a company called Keisub Electronics.

Hope this helps.

VegasCorbin

 

[EricCottrell]

Thanks Eric. I have been searching on google and came up with several results. The only problem that I have had with the results is that it is all in bulk. I only need 1 of these, and most of them are 100 or more. I found some sites who had a minimum order of $100 or more. I also found another one that ended in AP, but I have no idea what the P signifies or the (EL) that RS had beside of the component in their parts listing. Can you help me on any of these? I did take electronics class but that was 20 years ago. Needless to say, I didn't end up in that profession.

The P is the 16 pin Dip. You do not want that. The Toshiba datasheet shows the packages. You need the SOP-16 package.

I like dealing with Mouser because they allow you to do small orders. Looking at their website at http://www.mouser.com I see STMicroelectronics has this chip in the right package. You need a M74HC4094M1R. Mouser part number is 511-M74HC4094M. I would buy two at least and see if you need anything else.

Likely you will need some small solder wick and smal diameter solder to do the rework. Do not use that Weller soldering gun! You need low wattage.

73 Eric

 

[bby]

Here is a pic of what I have. It is not the clearest in the world, but it might give you an idea of what I have. Previous owner did a cell mod to this and messed up a leg of the chip. It was only working part time in the 400mhz band. The leg that was giving a problem was not really soldered to the chip, but laying up against it instead. This is a 2 sided board, but the chip only solders to one side. It does solder to the board instead of using a socket.

 

[EricCottrell]

Hello,

Yep looks like a SOP-16.

You need to be careful replacing the chip. The best method may be to take a pair of small diagonal cutters and cut the pins where they enter the body of the IC. Then take a pair of needle nose pliers and remove the leads from the pads.

This stuff can be delicate to work on so I suggest if you know someone who repairs scanners or does surface mount rework that you get the part and have them change it. You need the right tools, like a low-wattage temperature controlled soldering iron with a conical tip that goes down to a sharp point. You have to be careful about solder bridges, not overheating the chip or pads, etc.

73 Eric

 

[bby]

Thanks Eric. I checked locally today and could not find it. I got in from work and ordered a couple from Mouser. I should have them Wednesday and can get this thing going. I do have a friend who is an Elect Tech who is going to put in in for me. I took it to him the other day to see if he could reconnect the broken pin. I looked with a mag glass and there wasn't really anything there to reconnect, but he said he would try. After he got to see it, he recommended a new chip also. I am going to let him solder it in for me because it is too small for me, and I would go crazy with the small pins. Thank you guys very much.

 

[bby]

Just to update...I ordered 2 of these chips from Mouser. The only problem is that they are not as wide as the one that was in it, so it won't work. Man, I thought the old one was small, but this one is even smaller. The new chip is the same length, but it is not as wide. Friend said he could try clipping the legs off the old chip and connecting to them, but it was still too short. Guess I am gonna have to look for a different one.