Difference between revisions of "0/10/20/30 dB Attenuator"

Latest revision as of 20:41, 3 October 2021

DC-4.0GHz 200mW DC 4.0GHz RF Fixed Attenuator SMA Double Female Head 0dB 10dB 20dB 30dB

From the AliExpress listing
- $5 with shipping (2021-10)
Frequency range: DC - 4.0GHz
Maximum power: 23dBm (200mW)
Standing wave ratio: ≤ 1.20
System impedance: 50Ω
RF interface: SMA double female head (Outer screw inner hole)
Attenuation:
- Direct: 0dB (reference)
- Level 1: 10 ± 0.8 dB
- Level 2: 20 ± 1.1 dB
- Level 3: 30 ± 1.5dB

Characterized filters uinf NanoVNA
- 1 to 900 MHz (card spec is up to 4 GHz)
- Through-calibrated with SMA barrel and same cables was flat

Board uses 5% (3-digits) resistors
- Can result be 1dB with 5% resistors?
Tracks are wide but 50 Ohms?
0805 resistors limit power handling to 200 mW max
Lots of ground stitching
Compared to Homebrew attenuator
- Homebrew is more accurate in DC-100 MHz range
- Leads may act as inductors/capacitors

@@ Line 64: / Line 64: @@
 * Board uses 5% (3-digits) resistors
-** How can result be 1% with 5% resistors?
+** Can result be 1dB with 5% resistors?
 * Tracks are wide but 50 Ohms?
 * 0805 resistors limit power handling to 200 mW max
 * Lots of ground stitching
+* Compared to Homebrew attenuator
+** Homebrew is more accurate in DC-100 MHz range
+** Leads may act as inductors/capacitors
+[[file:ATTEN_30DB(HOMEBREWvsPURCHASED)_1MHz_TO_900MHz.png]]
+== Improvements in design ==