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Assembly:

Your work area should be reasonably clean and uncluttered. Good lighting is a must. 

Empty the packets containing the parts into small paper bowls. This will ensure that they do not get lost. Some 
people like to do the assembly over a cookie sheet, as the lip around the edge helps to keep parts from going far. 
The metal sheet also provides some measure of static control, especially if you ground it. A white sheet under 

your work area could help in finding a part which might get away from you. 

A very thin (0.015”) solder is supplied for soldering the surface mounted parts. Very little solder is need for each 
connection. Ideally, you want a little convex fillet at the end of chip resistors and capacitors. Try not to end up will 
a ball of solder at the end of the part.

Do not use liquid solder flux.

 It simply makes a mess and is difficult to clean off the board and get out from under 

parts. If not completely removed from the board, it can cause problems. 

Before placing a part, lightly tin one pad for where it will go. You can speed assembly by tining one pad at all the 
locations for which a particular value of part will go. There is no need for a low wattage soldering iron. It is best to 

have a hot tip which will let you get the job done quickly.  You will need a small tip on the iron, 1/32” to 1/16” 
chisel or round is best.

Most of the surface mount parts come in part carriers. To remove the part(s), hold the carrier close to the work 
surface and carefully peel back the clear plastic covering the part. This can be done with the tip of a sharp hobby 

knife such as a #11 Xacto blade or pointy tipped tweezers. Once you remove the clear plastic strip, dump the 
part out of the carrier and onto your work surface. 

If you use tweezers to handle the parts, be very careful you don't grab onto them too tightly. These little parts 
have a way of flying out from between the tips of the tweezers, never to be seen again. Apparently, they go into 
the twilight zone, along with all the pens, small parts and hardware which falls off the bench. They must go 

someplace since its never anywhere I can ever find them again!

An alternative to using tweezers to handle the parts is to use a tooth pick or chop stick with the end rubbed into 
a little bees wax. The bees wax makes the end sticky so the part will stick to it. For the smaller IC's I grab them 

length wise with the tweezers. 

Tack the end of a part in its place by applying heat to the end of the part over the tined circuit board pad, while 
applying a little pressure to make sure it lays flat to the board. Be sure to heat both the pad and the end of the 

part. Generally, you will not have to add any additional solder to this connection. Then solder the other end of the 
part. If you don't do this right away and go onto tacking down some more parts, there is a good chance you will 

forget to go back and solder all the parts which require it. 

It is nearly impossible not to make solder shorts between pins on the DDS chip, due to the close pin spacing. 
Remove any shorts with solder wick.

Using solder paste:

Using solder paste is the ideal way to build the board. Small amounts of solder paste in an application syringe can be 

bought for about $5.00 from Cash Olson over the internet. Also needed is a warming plate to preheat the board to about 
200 degrees and a low power heat gun. An “Embossing” heat gun is commonly used (found at craft stores), though a hair 

dryer on low setting might work. A soft air flow is required as to not to blow parts off the board. 

A very small dab of solder paste is put on the pads and then the part placed over the pads. The parts will slide 

around very easily, so one must be careful not to nudge them. The phono jacks and LED display should be hand soldered, 
along with all the through hole parts. Start with the back side of the board with the most parts first. 

Once all the parts have been placed, put the board on the warming plate and heat to about 200 degrees. Then 

slowly heat the top of the board with the hot air gun. When the solder paste reaches its melting point, you will see it 

liquefy and the parts snap into alignment to the pad. This is when the solder paste turns from a dull gray to shinny. Be on 
the look out for “tomb stoning” which is when a chip cap or resistor will stand up on one end. Once all the solder has 

reflowed, remove the power to the heating plate and let it cool down. 
 

A video showing how to hand solder SMT parts and how to use solder paste can be found on the CD and is 
viewable with Windows media player. The file is in the folder labeled “Video” 

Using the parts placement guides:

The parts placement guides on the following pages are color coded to show the location of the various parts. Parts which 
are not yet to be installed or already have been installed are colored the same as the background color. The guides are 

scaled so that the writing on them is easy to see on a computer monitor and come out crisper after the conversion to pdf. 
Unfortunately, if you print all these pages out, it will use up a bunch of your ink jet ink.  

2

Summary of Contents for Mountain Topper

Page 1: ...ncy trim and BFO adjustment 13 Receiver input peaking 13 Transmitter test and output low pass filter adjustment 13 Mounting into an enclosure 16 Basic operation 17 Turning the rig on and off 17 Volume control 17 Band selection 17 Control switches 17 Frequency tuning 18 Tuning limits 18 SPLIT MODES 18 MENU 18 Quick selections 18 DFE Mode 19 Tune Mode 19 Battery Voltage 19 MENU switch only selected ...

Page 2: ...ing heat to the end of the part over the tined circuit board pad while applying a little pressure to make sure it lays flat to the board Be sure to heat both the pad and the end of the part Generally you will not have to add any additional solder to this connection Then solder the other end of the part If you don t do this right away and go onto tacking down some more parts there is a good chance ...

Page 3: ...e also color coded but with a color sticker as they come in plastic carriers Again the color on the carrier matches the color shown on the placement guide diagram Resistors have their value printed on them though it might take a magnifying glass to read the numbers Therefore individual values are not color coded Various photos Using a straight edge to hold the TSSOP IC s in alignment with the pads...

Page 4: ...d to put component designations next to most of the chip resistors and caps Use the diagrams below to locate a part with its designation number Note Slide switches can be mounted on either the top or bottom of the board Top Side Bottom Side 4 Jumper between R14 and R13 added on final assembly ...

Page 5: ... L1 L2 L9 SMT 1206 2 18 uH 40M BRN GRY BLK GLD 2 12 uH 30M BRN RED BLK GLD 2 8 2 uH 20M GRY RED GLD GLD QTY Part number Color code or value location description 2 SA612A U1 U3 MIXER 1 LM4808M U2 AUDIO AMP 1 TC1014 3 3VCT713 BROWN A5xx last two characters are date code U4 3 3V REG 1 LM386M U5 AUDIO AMP 1 AD9834BRUZ U6 DDS 1 MCP1703 5002E DB MCP1703 U7 5V REG 1 74AC02M AC02 U8 QUAD OR 1 SN74LVC1G315...

Page 6: ...ut diagram U11 is the rectangular box with the silver top Be sure to get solder to flow into the little U shaped cups near each corner of the part A number of builders have had trouble with this and not made solder connection to the pads under the part A fine tipped iron is required here Also be careful of using too much solder and making a short to the metal top of the package D3 has very faint l...

Page 7: ...rs left over which go on the top side of the board Put these aside in a safe place until needed The approximate location in the table will help locate the position of the resistor values on the board upper middle lower is Y coordinates area while left center right is X coordinates Resistors R3 BS1 and R4 BS2 values depend on the band to be used see band value table below 7 Value places Approximate...

Page 8: ... a safe place for the time being light blue red stripe 1 Brown 1 Orange 1 Red 3 Blue 2 It is easy to confuse the orange caps 22 pfd with the Red 0 1 ufd caps on the layout digram so we will pace the orange ones first Part number start in upper left and run left to right top to bottom in a zig zag fashion 8 Location color places C18 30 32 68 Orange 4 C25 26 Yellow green stripe 2 C4 5 6 8 9 11 21 22...

Page 9: ...t confuse with Q6 2955 Q6 7 seg display LED Display Make sure decimal point is in lower right hand corner Once soldered in place the display is nearly impossible to remove Four trimmer capacitors labeled BNDB and BNDA now need to be installed before the through hole parts are mounted to the top side of the board CT1 is on the bottom side Install this one now Note the cut corners on one end of the ...

Page 10: ...hole caps Values shown in layout locations are for 40 and 20 meter bands If another band combination is desired change values as needed See table below for value 20M 40M 30M C60 104 0 1u C60 104 0 1u C60 104 0 1u C46 56 151 150 p C47 C57 331 330 p C47 C57 221 220p C51 331 330 p C52 681 680 p C52 561 560p C65 22p Orange C66 68 p Black C66 47p Brown C65 C66 already installed values shown for referen...

Page 11: ...ing Cut the insulated hookup wire to lengths about 1 5 long Install the wires to the top side of the board then connect to the corresponding connections on the jacks If mounting the board in an Altoids tin the jacks will mount as close to the bottom side of the board as possible In order for this to work the wires need to come off the top side of the board and wrap back around the edge to connect ...

Page 12: ...the off chance the stored values become corrupted The ideal reference frequency of 40 000 000 MHz is initially assumed to calculate the DDS VFO frequency In practice the reference oscillator has a 100 ppm tolerance This tolerance can cause an error between what the processor thinks the operating frequency is and what it really is The error would be most noticeable on the higher bands where the ref...

Page 13: ...transmitter and filter boards are working properly You can now go onto the testing and adjusting the band filters Otherwise go to the trouble shooting guide on page and track the reason the rig isn t working down Receiver input peaking The two trimmers labeled BNDB peak the band selected with the slide switches set to the right normally 20 Meters Like wise the two trimmers labeled BNDA peak the ba...

Page 14: ...de drop Output from 5V and 3 3 V regulators If not check connections and for shorts to ground Connections to U10 the processor Check power supply pins and X6 crystal connections The processor will not do anything except set the ports direction and state unless the 32 kHz clock is running Missing segments on LED display Check connections on R31 to R38 on the display and processor leads No receive C...

Page 15: ...V Tx key P6 1 7V osc P23 3 3V Tune up P7 3 3V reset P22 3 3V MENU P8 3 3V Tune dn P21 3 3V RIT P9 3 3V Dash in P20 0 3 3V Band volt P10 3 3V Dot in P19 5 to 1 2 Batt V P11 3 3V 7seg P18 3 3V 7seg P12 3 3V 7seg P17 3 3V 7seg P13 3 3V 7seg P16 3 3V 7seg P14 3 3V 7seg P15 3 3V 7seg U10 MPS430 MPU P1 1 13V FS ADJ P20 75V IOUTB P2 1 17V REF out P19 37V IOUT P3 1 76V COMP P18 0V AGND P4 3 3V AVDD P17 37...

Page 16: ...ill locate the holes for the jacks Drilling the thin sheet metal of the tin does not generally result in the cleanest holes The best results are obtained if you have a drill press You should always make a dimple to center to drill bit with a center punch or other shape pointy object Then drill a pilot hole using a small diameter bit say 1 16 This will keep the larger bits from wandering when you m...

Page 17: ...tually produce too much volume if your hearing is still good In this case an in line volume control can be added in series with your headphones Band selection Three DPDT switches are used to select one of the two bands the rig has been built for Make sure all three switches are in the same position i e to the right or to the left The switch near the top edge of the case tells the processor which b...

Page 18: ... RIT mode While RIT is active the display is used to show the approximate Rx frequency delta relative to the Tx frequency as illustrated by the diagram A 0 is displayed when Rx Tx frequency A side tone beep is also sounded when you tune back to the frequencies being equal When you tune above or below the Tx frequency but by less then 250 Hz the display will show When you tune beyond delta 250 Hz L...

Page 19: ...t carrier is not needed it is better to send a string of Dots then use Tune mode for adjusting a tuner Toggle transmitter on Tap the LEFT DOT paddle Toggle transmitter off Tap RIGHT DASH paddle Exit Tune mode Click Menu switch E annunciated Battery Voltage This mode reads the input voltage to the board and then displays it on the LED display and annunciated in Morse The letter B is sent before the...

Page 20: ...al and the upper right segment b will flash at the word space time out Paying attention to the flashing lights will allow you to enter a message without timing mistakes Checking and storing the message When you have finished keying in the messages click the Menu switch The message will then play back so you can check that they were entered correctly If the playback is good and there are no mistake...

Page 21: ...can be restored using the calibration mode which will also reset the initial power on frequencies Straight key mode Straight key mode is automatically detected and enabled when the rig is powered up when a monaural plug is in the paddle jack The sleeve of the mono plug grounds the dash input which enables straight key mode Straight key mode also allows use of an external keyer if one so desires Op...

Page 22: ...Schematics Receiver section 22 ...

Page 23: ...CPU TRANSMITTER Sections 23 ...

Page 24: ...un it Of course you do click yes A comprehensive operations manual for Pocketdigi has yet to be written Vojtech in waiting for someone to volunteer Most of the functions are self evident and intuitive working in much the same way as programs you are probably familiar with The screen is divided into three sections The top is the waterfall The operating frequency is set by tapping or clicking on the...

Page 25: ...n tones and can be heard in the headphones 4 Find the ATS 3B signal with the other receiver and select the signal on the waterfall Its AFC should also be turned off 5 Return to receive mode on the Pocketdigi by clicking the lightning bolt again 6 Transmit a signal with the other rig 7 Check the frequency of where the other rig is transmitting at on the Pocketdigi water fall Tune the transmit frequ...

Page 26: ... Notes taken from QSO data soft Software version Making QSOs Because the bandwidth of the MTR is so narrow you have to tune stations in to get them into the pass band Once in the pass band of the receiver and you have good copy on them you can match their frequency by taping on the waterfall This is very handy as the 50 Hz tuning steps are a little too coarse to exactly match other stations freque...

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