MC1496 AM Modulator Circuit - Working improperly?

I've been working on a lab for a while which uses the MC1496 IC. I built the physical circuit and was able to get it to operate properly, but I can't seem the get the PSpice simulation to behave the same way. I used two different models that I found online (one of which from this forum), which I used to build the Orcad Part. But based on this circuit's physical operation, the 50k potentiometer is supposed to increase and decrease the power in the carrier. If I adjust the offset voltage of the modulating signal from 0V to twice its amplitude, I can show everything from null carrier to under-modulation within PSpice. Yet I can remove that 50k pot entirely and it has no effect on the output?

Again, the resistor (R7 in my orcad circuit), is supposed to have some effect on the carrier, but instead has no effect at all.

I'll attach some pictures of the circuit I was building, along with the pspice circuit and MC1496 models. If anyone has any thoughts or suggestions, it would be greatly appreciated.

Thank you in advance!

-Negatorx



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MODEL #1
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.subckt MC1496 1 2 3 4 5 6 8 10 12 14
* Tail current Source
Q1 3 5 19 Q2nn
Q2 2 5 13 Q2nn
* Input transistors
Q3 7 4 3 Q2nn
Q4 9 1 2 Q2nn
*LO quad switching Transistors
Q5 6 8 7 Q2nn
Q6 6 10 9 Q2nn
Q7 12 10 7 Q2nn
Q8 12 8 9 Q2nn
* Emitter degeneration resistors
RE1 19 14 500
RE2 13 14 500
*
* Current Mirror
Q9 5 5 15 Q2nn
Rd 15 14 500
.ENDS
.MODEL Q2nn NPN(
+ISS=0 XTF=1 NS=1
+CJS=0 VJS=0.5 PTF=0
+MJS=0 EG=1.1 AF=1
+ITF=0.5 VTF=1 BF=280.92203
+BR=20 IS=2.3673E-15 VAF=130.20848
+VAR=11.074004 IKF=0.23419 ISE=3.0707E-16
+NE=1.19409 IKR=7.80101 ISC=3.5223E-12
+NC=1.33867 IRB=1.8864E-4 NF=0.97302
+NR=0.97623 RBM=1E-2 RB=69.94226
+RC=3E-02 RE=0.2569 MJE=0.36064
+MJC=0.29228 VJE=0.81795 VJC=0.45460
+TF=5E-10 TR=6.2636E-09 CJE=6.7441E-12
+CJC=3.4247E-12 FC=0.95 XCJC=0.95425)
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MODEL #2
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* Simple Spice model for an MC1496
.SUBCKT MC1496 1 2 3 4 5 6 8 10 12 14
Q7 3 5 20 Q2N2222A
R2 20 14 500
Q8 2 5 21 Q2N2222A
R3 21 14 500
D1 5 22 D1N914
R1 22 14 500
Q5 23 4 3 Q2N2222A
Q6 24 1 2 Q2N2222A
Q1 6 8 23 Q2N2222A
Q2 12 10 23 Q2N2222A
Q3 6 10 24 Q2N2222A
Q4 12 8 24 Q2N2222A
.ENDS

* Transistor model
.MODEL Q2N2222A NPN(Is=14.34fA Xti=3 Eg=1.11 Vaf=74.03 Bf=255.9 Ne=1.307
+ Ise=14.34fA Ikf=.2847 Xtb=1.5 Br=6.092 Nc=2 Isc=0 Ikr=0 Rc=1
+ Cjc=7.306pf Mjc=.3416 Vjc=.75 Fc=.5 Cje=22.01pf Mje=.377 Vje=.75
+ Tr=46.91n Tf=411.1p Itf=.6 Vtf=1.7 Xtf=3 Rb=10)

*diode model
.MODEL D1N914 D (IS=100E-15 RS=16 CJO=2PF TT=12NS BV=100 IBV=100E-15)
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This circuit is a (balanced) modulator but not AM modulator.

AM modulator is very similar but have 750 resistors around the 50k potentiometer.

Check the MC1496 datasheet.