Site Updated 5/19/2012
Scotts Electronic Parts
<>
I have started a Blog at
http://scottscrystalradio.blogspot.com
You can ask Questions, Give Ideas or Make Comments.
Members can give answers to questions as well as myself.
For Sale MK484 AM Radio IC
The MK484 MK-484 MK 484 is a AM radio receiver IC has automatic gain and up to 72 db gain. It is cased in a TO-92 Case looks like a transistor. The MK 484 runs on 1.1 to 1.8 volts so a single 1 1/2 volt battery will work. Also the MK-484 needs a tuning Capacitor and Ferrite Rod Coil or also known as a loopstick antenna we sell both items.
The MK484 Kits are TRF ( Tuned Radio Frequency, Tuned RF ) type receivers. This the most basic type of radio receiver with no regeneration or re-genitive feedback. The variable capacitor and antenna coil form a "Tank" circuit that tunes the radio stations frequency then the MK484 amplifies the radio stations radio frequency then "Rectifies" (Converts to Audio) it then amplifies the audio and powers the Earphone.
Yes a real MK484, not like other sites that sell MK484/TA7642. If you see this designation on other sites you are getting a TA7642 not a MK484.
I also have for sale the YS414, TA7642, UTC7642 and CD7642 sold separately at bottom of this page if you are looking for one of these instead of the MK484.
The YS414, TA7642, UTC7642, CD7642 are the same as the MK484 only different manufactures.
I do not ship equivalent parts if you order a MK484 I ship a MK484 not one of the others.
Contact Me At slowe15@cinci.rr.com
PayPal will let you pay with
a Credit Card without having to become a member.
I now accept all Major Credit Cards.
I use PayPal to process the payment.
Go to my Home Page for Shipping Charges.
I no longer ship Internationally, I only ship to USA addresses.
Except for a Business or Company with a UPS, FedEx or DHL account. Shipped using there account number. They must take full responsibility for the delivery from there carrier and pay all duties, customs taxes or other expenses involved.
Below is a link to MK484 schematics for the MK484 kits.
I hesitated selling the Kit Number 3 because it was not very stable for me when I connected to the center tap. However there are many kits that use the center tap on the coil so it must be able to work OK. You can also add the circuit to adjust the Auto Gain might help. You can also connect the variable capacitor Pin "A" to Point 1 and the MK484 input Point "3" to Point 1 also and leave the end of the coil Point "2" unconnected to cover the mid AM band from about 740 KHz about 2.2 MHz just a little into lower short wave bands.
The difference in Kit 3 and Kit 4 is the coil supplied, I also have 608uh Round rod coil with no taps that be swapped for the others if you want no taps on the coil just send me an email stating you want the 680 Round Rod Ferrite Coil. This keeps me from making another kit number.
Any coil in any kit can be swapped out for one of the others. If you do not want the standard supplied coil that comes in a kit send me email stating the coil you want with your kit. I have 3 choices 788uh with antenna tap and center tap , 680 with tap around 470uh ( this is the standard for all the Kits but Kit number 3) and a Round Rod 680uh with no taps.
MK484 Schematic Circuit Diagram for MK484-Kit-3.pdf
MK484 Schematic Circuit Diagram for MK484-Radio-Kit-4.pdf
MK484 Schematic Circuit Diagram for MK484-Kit-5.pdf
MK484 Schematic Circuit Diagram for MK484-Kit-6.pdf
The PDF file below shows how to add an adjustable auto gain control to the MK484
MK484 Circuit Diagram to adjust the Auto Gain MK484AutoGain.pdf
Internal Circuit Diagram for the MK484 MK484 Internal Circuit Diagram.pdf
Any of the above MK484 circuits will work with the YS414, TA7642, UTC7642, CD7642
For Sale MK484
MK484 Kit-3
Parts the same as in Kit-4 below only it has different Antenna Coil.
MK484 Kit-4
MK484 Kit-5
This kit comes with (Mono 2000 Ohm High Impedance Headphones). With 1/4 plug ends.
MK484 Kit-6
This kit comes with a High Impedance Ceramic Headphone. Wire mono with 1/4 inch plug end cord is about 40 inches long.
The Piezoelectric functions the same as a Ceramic Earphone. The are not the homemade Headphones sold on other sites with Piezo Transducers, these were made by a Headphone Manufacturer special for me.
Order Variable Capacitors Here. The MK484 Kits Use the 60/141pf Models.
Two Sizes Ferrite Rod Antenna ( Loopstick Antenna Coils )
Picture on left Flat Rod types 5mm X 12mm X 55mm long. Two sizes 788uh Tap at center and tap about 10 turns from end and 680uh tap at 470uh. Picture on right 680 round rod 10mm X 60mm long ( about 3/8 inch X 2-3/8 long) Price $2.47 Each
The MK484 Kits Use The 680uh With Tap At 470uh.
The diameter is about that of a dime.
The diameter is about that of a nickel.
Mono High Impedance Headphones with 1/4 inch plug ends. The High Impedance Headphones have an Impedance of 2000 Ohm making them ideal for the MK484 Ic or the YS414, TA7642, UTC7642, CD7642.
Mono High Impedance Piezoelectric Headphones with 1/4 inch plug ends. These headphones have an Impedance of over 20 million ohms. Factory made not homemade.
Part # 1/4Jack-1, Mono 1/4 Phone Jack for my High Impedance Headphones Price $1.97 Each
For Sale TA7642
TA7642 - Radio Kit ( Same as the parts as the above MK484 Kit-4) only comes with TA7642 instead of the MK484.
For Sale YS414
YS414 - Radio Kit ( Same as the parts as the above MK484 Kit-4) only comes with YS414 instead of the MK484.
For Sale CD7642
CD7642 - Radio Kit ( Same as the parts as the above MK484 Kit-4) only comes with CD7642 instead of the MK484.
For Sale UTC7642
UTC7642 - Radio Kit ( Same as the parts as the above MK484 Kit-4) only comes with UTC7642 instead of the MK484.
Contact Me At slowe15@cinci.rr.com