Sinclair Isolators
Sinclair isolators protect a repeater or base station transmitter from reflected power and stop other transmitters’ signals mixing inside it. That cuts intermodulation interference on shared hilltop sites. Single and dual stage models are available for VHF and UHF, each optimised to your transmit frequency.
- VHF 132–174 MHz (5 MHz bandwidth) or UHF 406–512 MHz (12 MHz bandwidth)
- Single stage, or dual stage for higher isolation
- Temperature compensated, low insertion loss
- Tuned to your specified frequency
Why use an isolator?
On a shared radio site, signals from nearby transmitters travel down your aerial into your transmitter's output stage. There they mix and create intermodulation products that can interfere with your own and other users' receivers. An isolator is a one-way device: it passes your transmit signal to the aerial with little loss and sends anything coming back into a load. It also protects the transmitter from high VSWR if an aerial or feeder is damaged.
Single or dual stage
A single stage isolator suits most repeaters and base stations. A dual stage isolator adds a second section for much higher isolation, for crowded sites or where a site owner requires it. On Sinclair's VHF models, a single stage gives about 25–35 dB of isolation and a dual stage about 50–75 dB.
Tuned for your frequency
Each Sinclair isolator is temperature compensated and optimised to the frequency you specify. VHF models cover 132–174 MHz with a 5 MHz bandwidth, and UHF models cover 406–512 MHz with a 12 MHz bandwidth. Send us your transmit frequency when ordering.
Complete the site
Combine an isolator with a duplexer, cavity filters, Procom duplexers and lightning protection for a clean, reliable repeater site. Signals NZ designs, installs and services radio sites across New Zealand.
Models
| Model | Stages | Frequency range | Bandwidth |
|---|---|---|---|
| I211(X)A | Single | 132–174 MHz | 5 MHz |
| I221(Y)A | Dual | 132–174 MHz | 5 MHz |
| I311(X)A | Single | 406–512 MHz | 12 MHz |
| I321(Y)A | Dual | 406–512 MHz | 12 MHz |
All models are temperature compensated and optimised to the customer's specified frequency.
Additional information
| Brand | Sinclair |
|---|---|
| Band | UHF, VHF |
| Model | I211(X)A – VHF single stage, 132–174 MHz, I221(Y)A – VHF dual stage, 132–174 MHz, I311(X)A – UHF single stage, 406–512 MHz, I321(Y)A – UHF dual stage, 406–512 MHz |
