An upgrade for NE602AD is SA602AD . The NE prefix part has a temperature range of -0°C ~ 70°C and the SA prefix is -40°C ~ 85°C. All of the other specifications would be the same.
Digi-Key Part Number 568-1200-2-ND
NXP USA Inc SA602AD/01,118
| RF Type | Cellular, HF, UHF, VHF | |
|---|---|---|
| Frequency | 500MHz | |
| Number of Mixers | 1 | |
| Gain | 17dB | |
| Noise Figure | 5dB | |
| Secondary Attributes | Up Converter | |
| Current - Supply | 2.4mA | |
| Voltage - Supply | 4.5V ~ 8V | |
| Mounting Type | Surface Mount | |
| Package / Case | 8-SOIC (0.154", 3.90mm Width) |
Please review the datasheets to ensure the alternative will work for your application.