What is a 700/800 MHz Stubby Antenna?
A 700/800 MHz stubby antenna is a band-specific antenna optimized for the 700-900 MHz frequency range. The most popular model for the Uniden SDS100 and SDS150 is the Remtronix REM-820S, which delivers +6dB gain over the stock wideband antenna on these critical public safety bands.
Technical Specifications (Remtronix REM-820S)
| Specification | Details |
|---|---|
| Frequency Range | 700-900 MHz (optimized for 800 MHz) |
| Length | 7 inches (compact/stubby design) |
| Gain | Minimum +6dB over stock antenna |
| Connector | SMA Male (fits SDS100/SDS150 directly) |
| Design | Flexible whip rubber ducky |
| Impedance | 50 ohms |
| Water Resistance | Includes O-ring for moisture control |
| Compatibility | SDS100, SDS150, BCD436HP, BCD396XT/T |
When This Antenna Works Best
- P25 Trunked Systems (700/800 MHz): The primary use case - dramatically improves reception on modern public safety trunked networks
- Simulcast Environments: Better signal strength helps the SDS100's True I/Q receiver decode simulcast systems more reliably
- Weak Signal Areas: The +6dB gain extends your monitoring range significantly
- Urban Scanning: Cuts through interference better than wideband antennas in congested RF environments
- Commercial UHF (450-470 MHz): Also performs well on UHF business bands
Performance on Different Systems
P25 Phase I/II (700/800 MHz)
Excellent Performance. This is where the 820S shines. Clearer audio, better decode rates, extended range on trunked systems. Many users report receiving departments they couldn't hear with the stock antenna.
DMR Trunked/Conventional (UHF)
Good Performance. Works well on DMR systems in the UHF and 700/800 MHz range. Improved signal strength translates to better digital decode.
Commercial UHF (450-470 MHz)
Solid Performance. The 820S also delivers improved reception on commercial UHF bands, making it versatile beyond just 700/800 MHz.
VHF-High / Airband
Poor Performance. Not designed for VHF. If you need VHF/airband, use a telescoping whip or VHF-specific antenna instead.
Advantages & Limitations
✔️ Advantages
- Minimum +6dB gain on 700-900 MHz
- Dramatically outperforms stock antenna on P25
- Improves simulcast decode reliability
- Extends monitoring range significantly
- Compact 7-inch length (portable)
- Includes O-ring for water resistance
- Made in Japan - high quality construction
⚠️ Limitations
- Not suitable for VHF-high monitoring
- Poor on airband (108-137 MHz)
- Single-band focus (not wideband)
- Requires antenna swapping for VHF
- Costs extra (~$30-40)
Real-World Performance Reports
Scanner enthusiasts consistently report significant improvements with the Remtronix 820S:
- "Immediately able to receive departments the SDS100 did not receive with stock antenna"
- "Clear audio with only minor noise on a few channels - stock had nothing"
- "Great improvement over factory standard antenna"
- "Works extremely well on 700/800 MHz P25 systems"
These are common experiences shared on RadioReference forums and scanner communities.
Comparison: Stock vs 820S
| Feature | Stock Wideband | Remtronix 820S |
|---|---|---|
| 700/800 MHz Performance | Adequate | Excellent (+6dB gain) |
| VHF Performance | Adequate | Poor (not designed for VHF) |
| Simulcast Decode | Good | Better (stronger signals) |
| Length | 4-5 inches | 7 inches |
| Cost | Included | $30-40 extra |
| Best For | Mixed scanning | 700/800 MHz P25 focus |
Should You Upgrade to the 820S?
Upgrade if you:
- Primarily monitor 700/800 MHz P25 trunked systems
- Experience weak signals or missed transmissions on trunked channels
- Live in simulcast areas with decode issues
- Want maximum performance on modern public safety systems
- Don't need VHF-high/airband coverage
Stick with stock or consider alternatives if you:
- Monitor multiple bands (VHF + UHF + 800) regularly
- Need airband reception (use telescoping whip instead)
- Prefer not to swap antennas based on what you're monitoring
Installation & Compatibility
The Remtronix 820S features an SMA Male connector that threads directly onto the SDS100 and SDS150 antenna port - no adapters needed. The included O-ring maintains the scanner's water resistance.
Compatible scanners:
- Uniden SDS100
- Uniden SDS150
- Uniden BCD436HP
- Uniden BCD396XT/T
- Other scanners with SMA Female antenna ports
Frequently Asked Questions
Will the 820S work on VHF?
No. The 820S is designed for 700-900 MHz and performs poorly on VHF-high (150-174 MHz) and airband (108-137 MHz). For VHF, use the stock antenna or a VHF-specific antenna like a telescoping whip.
How much better is it than the stock antenna?
The 820S delivers minimum +6dB gain on 700-900 MHz compared to the stock antenna. In practical terms, this means significantly stronger signals, better decode rates, and extended range - many users report receiving departments they couldn't hear before.
Will it help with simulcast distortion?
Yes, indirectly. The SDS100's True I/Q receiver does the heavy lifting for simulcast, but the 820S provides stronger signals which give the receiver better data to work with. This often results in improved decode reliability in simulcast environments.
Is the 820S waterproof?
The 820S includes an O-ring that maintains the SDS100/SDS150's water resistance rating. It's weather-resistant but not fully waterproof - same as the scanner itself.
Where to Buy
The Remtronix 820S is available from scanner specialty retailers:
Link coming soon
Explore More Antenna Guides
Learn about other antenna options for your Uniden SDS100 and SDS150: