> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# GSG-Opera-Cake

**Type:** Product page · **SKU:** GSG-OPERA-CAKE · **Brand:** [Great Scott Gadgets](https://core-electronics.com.au/brands/great-scott-gadgets-australia)
**Page:** https://core-electronics.com.au/great-scott-gadgets-opera-cake-antenna-switch-for-hackrf-one.html ([markdown](https://core-electronics.com.au/great-scott-gadgets-opera-cake-antenna-switch-for-hackrf-one.html.md))

Antenna-switching board for SDRs that automates port routing by frequency or time across 1 MHz to 4 GHz, optimised for multi-antenna sweeps.

## Pricing

- **Price:** $309.95 (inc GST) — $281.77 AUD, exc GST

## Availability & dispatch

- In stock, ships same business day if ordered before 2PM (Australia/Sydney).
- We can dispatch 1 today; more stock is typically available with a 7–14 day lead time.

## How to buy

- **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=GSG-OPERA-CAKE:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart.
- **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/GSG-OPERA-CAKE:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.)
- **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there.
- **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works)
- **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt
## Description

Switch antennas in software, not with a spanner. Opera Cake is the antenna-switching add-on [for HackRF One](https://core-electronics.com.au/great-scott-gadgets-hackrf-one-software-defined-radio.html) that makes multi-antenna SDR workflows fast, neat, and repeatable.

Use it to automate port selection by frequency or time, route TX to the right antenna and inline RF hardware, and even switch antennas mid-sweep for wideband spectrum scans with hackrf\_sweep. Its architecture supports either one 1x8 or two 1x4 switching topologies, giving you flexible RF plumbing without touching a cable.

### Technical Specifications

- Switch topology: two primary ports selectable to any of eight secondary ports; optimised as 1x8 or dual 1x4.
- Recommended frequency range: 1 MHz to 4 GHz.
- Control: command-line configuration; manual switching or automated by frequency or time.
- TX integration: can auto-route HackRF One transmit output to selected antennas and external filters, amplifiers, etc.
- Spectrum analysis: compatible with hackrf\_sweep; supports automatic antenna changes mid-sweep.
- Software impact: no changes required to existing SDR applications; full host control available.
 
### Additional Resources

- [Read the Docs](https://hackrf.readthedocs.io/en/latest/opera_cake.html)
- [Opera Cake hardware design files (GitHub)](https://github.com/greatscottgadgets/hackrf/tree/master/hardware/operacake)
 
### What’s Included

- Opera Cake antenna switching add-on board for [HackRF One](https://core-electronics.com.au/great-scott-gadgets-hackrf-one-software-defined-radio.html).

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/g/s/gsg-opera-cake.jpg)