Welcome to the

The building of
"Multi-pig+ Ser #21"
by fp # 567 kc5wa
Robert "RC" Conley

The MultiPIG+ is the ultimate QRP transceiver 10 bands and .1-5w output.
An experimenters QRP radio. designed by Dieter Gentzow, W8DIZ and built on seven pcb's.
Check out Diz's web site all schematics parts list and instructions are available there.
They are copyrighted and used here with his kind permission.

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L1 installed the hardest part first a 4:1 transformer. It took me 3 tries to get it correct

Now per Diz's instruction we'll install the resistors. The way it works best for me is install them like you're reading a book
left to right top to bottom. makes it easier to trouble shoot also. Because of the number of odd value resistors each was checked
with my DVM BEFORE it was soldered in, and only one component at a time. It takes longer but less chance of goofin'up. [g]

Resistors installed on PLL PCB and hi-lited on the schematic in pink

all headers have been installed except the 2 x 10

here the voltage determining network has has been installed....

(Now from the instructions)
"Apply power 12-14 vdc to the header in the lower right corner. The left most pin is plus (+) and the other two pins are GROUND.
Suggest you use the the header socket and solder a white wire to the PLUS (+) and a BLACK wire to one or both GROUND pins.
With power applied, measure the voltage at PIN-3 of the PLL, U4. It should be near 8 volts. Measure the voltage on the (+)
side of C24 in the center of the board. It should be near 9.7 volts. This completes the power supply circuit."

APPLIED VOLTAGE...............12.74 VDC
U4 PIN 3 MEASURED..............7.91VDC

On the schematic hi-lited in yellow you can see voltage network and the test points, hi-lited in orange most of the
capacitors with the exception of the capacitor bank and the 2 x 10 header have been installed

next the capacitor banks the 2 x 10 header, then the discreet components.....

the varible capacitor and the 2 x 10 header have been installed

All the discreet components are installed. A partial finish is dictated here by Diz for some theory then
alignment of the PLL board.
Initial test of the PLL on the 10m of the capacitor bank is good.
Finished installing the 9 fixed capacitors in the capacitor banks.

The Pll board is now complete. Testing and adjustment of the PLL capacitor bank is also completed

Discreet components hi-lited blue
capacitors hi-lited orange
resistors hi-lited pink

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Crystal and resistors installed. Each resistor was checked for value with my DVM before installing because of my old eyes and the size of the 1/8 watt resistors

All diodes and capacitors have now been installed

transistors, voltage regulators and headers have been installed

LCD display has been hooked up. it is detachable thank goodness because I most likley did it incorrectly.
U2 also installed

Now it time to test power supply-voltage regulators

From the instructions
Apply 12 volts to J10
You should measure 5 volts on pin 6 of U50.....actual measurement was 5.9 volts
and 5.5 volts on the center pin of U5.....actual measurement was 5.5 volts
and 8 volts on the right pin of U2.....actual measurement was 7.94 volts
If any of these voltages are different, STOP and recheck your work. Remove power from the FCC

actual construction has been completed now that the IC's have been installed along with the potentiometers

resistors are hi-lited yellow
diodes are hi-lited in pink
capacitors are hi-lited in blue
descreet components, transistors, voltage regulators and headers are hi-lited orange

The calibration of the frequency counter seems to be complete. All tests, checks, measurements and
adjustment have been completed. What's next?

During the calibration of the Frequency Counter Controller of a "Multipig+" a known frequency source
was required. I ordered this little $4.95 Crystal Oscillator kit from Nightfire Electronics. The kit
consisted of a Very good quality double sided PCB and a schematic. Building took less than an hour.
I used Augar machined pins in the crystal position so that I could swap out crystal if needed. The
oscillator delivered a rock hard signal for each of the five crystal that I used and measured with
my DSI frequency counter. The oscillators signal could also be heard LOUD AND CLEAR in my genera
coverage receiver 10 feet away. Crystals used were: 3.686 mhz, 7.040 mhz, 10.060 mhz, 14.060 mhz,
and 21.060 mhz. Here is the finished PCB for the Crystal Oscillator

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I've only installed the Band Pass Filter for the
forty meter band the others will be done after
the receiver and transmitter boards are completed.
I guess I'm in a hurry to put it on the air as this
one filter required 3.5 hours for me to construct it.

Here is the completed Band Pass Filter PCB. At least as complete as I'm going to build it. I left off the 17m and 60m bands.

Here is the Band pass Filter schematic

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INVENTORY all the parts against the parts list.
Be careful not to loose the 2 small short wires in the wire bag.

Inspect the PCB. You will find two errors in the layout...
1. A cut in the trace on the back of the PCB behind L9 (lower middle) We will add a jumper wire after all the other parts are installed.

2. A cut in the trace between R36 and C45 on top in lower left corner. We will add capacitor C45 after all the other parts are installed.


This modification was added to improve the PLL output waveform.
It your PCB does not have a TRACE CUT on the top of the board from
PIN 2 of J3 to the lower connection of L5, then do so now.

We will solder R21 across the CUT after all the other parts are installed.

U1 & U2 the SMT mixers ( white squares )are installed. Beleive me I like 'Roids better than SMT'S

Now all the resistors have been installed

Just wound and installed the toroids (all nine) and checked the solder connections with my piezo tester

Installed the capacitors

Finished the headers

All the discreet components along with crystals and varactors have been added

Look close at the top of the pcb and you'll see the white wire, this is a
test lead between D5 & D6. I added it now just in case it was needed. It would
have been more difficult later. Also on the bottom of the pcb C45 the 220pf
capacitor was added to corrected an error noted earlier along with white jumper
also to correct an error. A 51 ohm (R21) resister is also added per the instructions

12vdc was applied to the center pin of J6 and voltage was checked on pin #1 of J12 it should read 8vdc. The reading was 7.94vdc

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You can see the progress on this full schematic

Resistors are hi-lited in yellow as are the SMT's and the discreet devices and crystals
'Roids are hi-lited in blue
Capacitors in pink
Headers in orange

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Here's the low pass filter pcb with the 40 meter portion installed. Other bands will be installed at a later time.

Well! I guess that does it. The LPF pcb has been completed. At least as much as I want. Yes, the 17m and 60m band portion were left off.


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I've installed the headers and the resistors at this point. The headers
were easier for me this way because they could be aligned while soldering
as no other parts were on the pcb.

I just finished winding the three inductors( L1 L4 L5), one toroid transformer(L3) and the real
"booger" a bifilar transformer (L2).

The discreet components have been installed at this time

And finally the capacitors and mods

which you can see on the bottom of the XMTR PCB here

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Check my progress on the full transmitter schematic

Headers and discreet components arehi-lited in blue.
Orange on the resistors.
Yellow for the Roids
Pink for the capacitors

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Installed the resistors, headers and diodes

Capacitors, Pots, 'Roids and IC's now complete

SWR/PWR pcb Now completed

The complete SWR/PWR schematic

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#1 I ordered the incorrect size.I should have ordered a 17" x 10" x 3"
instead of the 14" x 10" x 3" I did order. The only differance I am able
to see at this time is lack of expansion room. This is my proposed layout. The picture was done
using my scanner and is as close to scale as I can get.



the only rear panel connections should be antenna and power. All other controls including
key and paddles should be on the front panel or the area on the top in front of the RCVR
and TX modules. This way I don't have to keep turning everything around to access the rear panel. I
hate that.


Picture of PLL board mounted on chassis

Picture of FCC board mounted on chassis next to PLL board. These boards will be swapped with each other

Picture of BPF board mounted on chassis far left only 40 meter band
has been installed at this time Notice also the incomplete
receiver board on the bench it will be installed between the PLL
and the BPF boards when completed.

Two pictures showing the completed receiver pcb mounted on the chassis.
Notice also that the FCC & PLL pcbs have been swapped and the addition
of the LCD read out and back lite switch have been added

These next two pictures show the LPF installed on the chassis.
They were taken using a pc camera. Some 35mm pictures will soon replace them.

Notice the yellow sticky notes show where the XMIT and SWR/PWR pcb's will be placed

Interconnection cables. Shown here are the ones made using RG-174 only 10 of these required.
Using a nominal length of 9" and spliting the shield to make dual grounds on the cable should
improve RF grounding. Most of the interconnects are just regular wired. Here is the
list of interconnections cables, jumpers and controls needed.

Interconnection cables

Hooking up the interconnection cables, also the installation of the 10 turn pot for VFO

The switch above the back lite switch is the IF +/- switch

The interconnection cables are only partially installed

Still working on the interconects and the controls. Installed the keyer speed and memory controls switches along with the keyer plug socket a mini stereo.

The lables above each control read R to L: VFO, VOLUME, MEM, SPEED PADDLES. The first control on
the right will be power switch. The remaining three will be BANDWIDTH, KEY AND RIT. Rear panel will be
POWER, ANTENNA. SPEAKER. (Jan 10, 2004) All the interconnection cables are complete with the exception of those that
connect to the xmit board as it is awaiting construction. A 12vdc 2ah battery has been connected and I
have power to all board needing power the back lite for the FCC display lites as does the lock L.E.D.
on the PLL board. now to attach a speaker looking for noise....[g] When I attached a speaker and turned on the power
the keyer sounded off to let me know it was ready with a dit dah dit. So something is working hopefully correctly.

You can see the chassis under side where I brought all the power connections together and added
a polarity protection diode between the two lower terminals in the left picture.

See the snake nest( cables everywhere) in the bottom

two views of the top and front

Well it looks like construction is finished now all that need to be done is
alignment and fine tunning and on the air contacts [g] so I may get my "piggy" ser #

Here on the left is my "piggy's pen" it's birth place so to speak and on the right there is me "rc".

IT HEARS............
IT HEARS............
I can hear the colpitts oscilator at 7.03965mhz and my SMK-1 at 7.04057
I tapped the SMK's and heard its "burp" in the head set.
The VFO actually dials up a frequency now.....

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Trouble shooting the MP+ XMTR

Since so many difficulties are caused by "L2" being
improperly wound let's take a look at it here.

a visual presentation of "L2" as I did it and be
able [g]explain it. The Blue indicates solder traces,
point "A" goes to C6, point "C" goes to C10,
point "B" goes to C13.

--after winding "L2" you should have a pair of wires
coming down the inside of the 'Roid
and a pair of wires coming down the outside of the 'Roid.

Take a wire from the inside pair place it through "point A".
Now take the other color wire of the outside pair place it
through "point B".
The two wires that are left ( one of
each color) are to placed through "point C" when finsished
you should be able to measure a "short" from C6 to C13 with
a VOM.


There is one other point to check before going much further
and that is the interconnection cable that connects J12 on
the RCVR PCB to J1 of the XMTR PCB

This rough drawing shows how it should be wired and the
reading for each


Now the transmitter schematic

Q1 ( 2N3906 ) is part of the keying circuit. When it is
activated by voltage from J1 pin 3 either from the keyer
or the tune switch it allows the transmitter to transmit
a signal of the desired frequency.

That signal arrives on J3 pin 2 and is routed into U1
via pins 2 & 3 and out on pin 6 amplified. The signal
travels across R12/C11 to the base if Q3 and it comes
out the collector of Q3 amplified still more. Through
"L3" a step up toroid transformer again amplified to
the base of Q2 out the collector to "L2" to the "LPF"
via J2 pin 2 then to the antenna.

If this is correct then I should be able to measure and
see gain using my scope and a full wave RF probe at the
following points in this sequence:

1..J3 pin #2
2..Junction of R7/C9 (slight decrease in signal
strength from step 1)
3..Junciion of R14/U1 pin 2(slight decrease in signal
strength from step 1)
4..Junction of R9/U1 pin 3 ( note reverse phase of step 3)
5..Junction of R12/U1 pin 6 (amplified from steps 3/4)
6..Junction of R11/ Q3 collector(amplified from step 5)
7..Junction of R13/base of Q2 (amplified from step 6)
8..Junction of C10/L3 (no change in amplitude)
9..Junction of C6/J2 pin 2(no change in amplitude)

The test equipment I'll use: A HB full wave RF probe and a hitachi 20mhz dual trace
scope this series makes me wish I had two full wave probes

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Guess what? NO SIGNAL WAS FOUND. Therefore a different tact was required.
My friend Ron Davis (WB5TGF )had dropped by and and took an interest in the hair
pulling that I was doing and I showed him that no signal was present in the
transmitter. Ron asked if I'd tried injecting a signal? Well I had not but
during the calibration of the Frequency Counter Controller of the "Multipig+"
a known frequency source was required. I ordered this little $4.95 Crystal
oscillator kit from Nightfire Electronics. The kit
consisted of a Very good quality double sided PCB and a schematic. Building took less than an hour.
To confirm this...Ron and I fed the output of the colpitts oscillator
with a 7.040mhz crystal into the receiver side of the BPF through the BPF into
the XMTR PCB out of the XMTR into the LPF out of the LPF into a DUMMY LOAD OF
A #47 lampw/ a 10ohm shock resistor

AND LITE THAT HUMMER UP!!!!!! The in-line DVM measured
.820DCA output about 9+ watts. Confirming that the BPF,
the XMTR and the LPF were indeed functional. You can check
indiviual bands as long as you have the crystal for the oscillator.Nice!

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I deceided to give myself a face lift. I really needed a cover. Even though I was being used. I have a tendency to
operate only on one band and this Piggy wasn't moving around very much and "OLD RC" was starting to complain about "DUST"?
A word or two was also said about my spartan appearance by a fellow "HAM" ("RC's" brother-in-law).

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Whenever you start anything like this you must have before and after pictures.

Soooo! Here's before shots of Me (Multipig+ #21). That "OLD DUDE" in the T-shirt is "RC"

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I started looking at enclosures as opposed to "chassis". I was tired of having my innards exposed all the time. I
finally deceided on a TENTEC enclosure. Model #BK-949. Basic Black for this PIGGY Now to pry "RC" away from that "K1"
he purchased from Elecraft.

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my PCB's on the enclosure floor plate which is adjustable in height

Sides and bottom clam shell added. Neat huh?

Interconnects installed

Frontal view

Once more an inside check

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All decked out for the party. Even a little wood trim. YA HOOOO!!

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72/71 DE "RC" KC5WA

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The building of "THE MULTIPIG+" is the ultimate QRP transceiver 10 bands and .1-5w output PLUS (some bands as high as 15w).
It has also been the ultimate test of my abilities and has taught me a lot in the process of it's construction these past
six months. It has also required a lot of hair pulling on my part and huges amounts of coaching from other MULTIPIG+ builders


JERRY FORD, N0JRN, Without whose devoted help and incourgement it would have entered the recycle can months ago.
Dennis Ponsness, WA0WAO whose Multipig + Mods inspire me.
RON DAVIS WB5TGF Pointing out the obvious on several occasions.
NIGEL A GUNN G8IFF / KC8NHF Who helped keep me going in the right direction.
And all the MULTIPIG+ builders for asking the questions that I didn't know to ask and putting THEM on the
Yahoo multipigplus user's group site. It really helped me
Tnx "RC" KC5WA

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During the calibration of the Frequency Counter Controller of a "Multipig+" a known frequency source
was required. I ordered this little $4.95 Crystal Oscillator kit from Nightfire Electronics. The kit
consisted of a Very good quality double sided PCB and a schematic. Building took less than an hour.
I used Augar machined pins in the crystal position so that I could swap out crystal if needed. I
oscillator delivered a rock hard signal for each of the five crystal that I used and measured with
my DSI frequency counter. The oscillators signal could also be heard LOUD AND CLEAR in my genera
l coverage receiver 10 feet away. Crystals used were: 3.686 mhz, 7.040 mhz, 10.060 mhz, 14.060 mhz,
and 21.060 mhz. Here is the finished PCB for the crystal oscillator

And the schematic that came with the kit, note that the Q1 and Q2 transistors were subsituted using
a 2N3904, even a 2N2222 will work here.

The PCB and schematic are copyrighted and used with the authors permission

72/71 DE "RC" KC5WA