North W 5 HN Texas NTMS Microwave Society

North W 5 HN Texas NTMS Microwave Society Microwave Frequency Standard Jim Hudson WA 5 JAT Ham. Com June 2010 WA 5 JAT 1

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society • Why Do we Need a Frequency Standard? • Remember the 100 KHz Calibrators on HF? • The Same Issues Exist on the Microwave Bands • Uncertainty in Frequency (+/-100 KHz at 24 GHz) • High Gain Antennas for Microwave Bands • <3 Degree Beam Width • Uncertain Rover Station Locations • Too Many Things to Monitor: • Antenna Elevation/Azimuth • Frequency Dial + Readout • “Hopefully”, Copy a CW Signal “In The Noise” Doing All These at Once is “Not Fun” Having a Precision Frequency Standard and Eliminating the Frequency Uncertainty is a BIG Help WA 5 JAT 2

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society Surplus Equipment is Available!!! RFG-M-RB & RFG-M-XO (EFRATOM Labels on PCBs / LUCENT on Panel) Rubidium Std RFG-M-RB Crystal Oscillator RFG-M-XO Rubidium Std (RB) outputs to XO which locks to the RB WA 5 JAT 3

Microwave Frequency Standard W 5 HN RFG-M-RB North Texas NTMS Microwave Society These Screws Release the Rb unit from the tray 15 MHz Output 10 MHz Output WA 5 JAT P 1 = DB 9 Male Power Connector Pin 1 = +24 VDC Pin 2 = Common 4

Microwave Frequency Standard W 5 HN RFG-M-RB North Texas NTMS Microwave Society Rear Panel Removed Rubidium Std WA 5 JAT House Keeping Sub-Unit 5

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society RFG-M-RB These Screws Release the RB Sub-unit after Rear panel removal The RB Sub-Unit Slides Sidewise and Unplugs WA 5 JAT 6

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society LPRO-101 10 MHz Sine Output WA 5 JAT 7

Microwave Frequency Standard W 5 HN Supplier Specification Sheet North Texas NTMS Microwave Society Source: http: //www. datasheetarchive. com/ WA 5 JAT 8

Microwave Frequency Standard W 5 HN Comparison of Several Frequency Sources North Texas NTMS Microwave Society Source: http: //www. leapsecond. com/museum/manyadev. gif WA 5 JAT 9

Microwave Frequency Standard W 5 HN Comparison of Several Rubidium Sources North Texas NTMS Microwave Society Source: http: //www. leapsecond. com/museum/lpro/ WA 5 JAT 10

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society How Do You Use 10 MHz for a Microwave Frequency Standard? • Direct Digital Synthesis (DDS) • Phase Locked Loop Followed by Multipliers to the Band of Interest WA 5 JAT 11

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society Direct Digital Synthesis (DDS) 10 MHz In – 96 MHz Output Source: NTMS FEEDPOINT Vol. 21, Issue 2 / WW 2 R WA 5 JAT 12

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Phase Lock Loop (N 5 AC/Down East Microwave) 10 MHz in - 1152 MHz Output (And 49 Others Available) Society Frequency Selection Jumpers Source: http: //www. downeastmicrowave. com/PDF/A 32_pd. pdf Also See: http: //www. n 5 ac. com/apol. LO-32 Operation. pdf WA 5 JAT 13

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society Example of a Frequency Multiplier Source: http: //www. w 1 ghz. org/MBT/multiband. htm WA 5 JAT 14

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society Questions? WA 5 JAT 15

Microwave Frequency Standard W 5 HN RFG-M-XO North Texas NTMS Microwave Society Front View Back View (Rear Panel Removed) WA 5 JAT 16

Microwave Frequency Standard W 5 HN RFG-M-XO North Texas NTMS Microwave Society Top View WA 5 JAT 17

Microwave Frequency Standard W 5 HN RFG-M-XO North Texas NTMS Microwave Society Bottom View WA 5 JAT 18

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society Internet Search Came Up with: ]> To: "Discussion of precise time and frequency measurement" Back when these Lucent units were first appearing GPS had not yet been Ø> implemented at the cell sites here in Alaska. The rubidium was too noisy Ø> for direct frequency synthesis, so the XO unit was phase locked to the rubidium Ø> to provide the long-term stability needed, and the XO output was Ø> up-converted for the system clock. By using the XO to smooth the rubidium Ø> output the phase noise in the system clock was reduced due to better Ø> short-term stability in the XO. As I remember it (It's been a while) the Ø> 10 M Rb disciplined the 10 M XO, which was divided by 2, multiplied by 3, Ø> filtered, and supplied as the 15 M system clock. The XO was always Ø> supplying the 15 M system clock, and "standby" just meant the XO was locked to the Ø> rubidium, which was acting as the primary frequency reference. When the Ø> rubidium failed the system alarm output went high, XO PLL went into hold, Ø> the standby light on the XO extinguished, and the undisciplined XO became Ø> the source until the rubidium could be replaced. The GPS connection didn't Ø> appear until later units and disciplined the XO during normal operation, Ø> with failover on extended GPS loss to disciplining the XO from the Ø> rubidium. WA 5 JAT 19

Microwave Frequency Standard W 5 HN North Texas NTMS Microwave Society Internet Search Also Came Up with: Sent: Monday, October 31, 2005 4: 56 PM Subject: Re: [time-nuts] Unknown Efratom 10 MHz Assy, information asked > The board you are describing is used in the Lucent RFG-M-XO reference > frequency generator. It takes in 10 MHz on J 2 from a Rubidium oscillator and > disciplines the Efratom SC cut OCXO on the main board from the 10 MHz input. > The output from the OCXO is converted to 15 MHz and supplied as the Øreference output on J 4. Ø> The RFG-M-RB and RFG-M-XO normally mount together in a chassis (which I didn’t Ø> get) and the modules are connected to the chassis by a harness with a > DB 15 on the chassis end. The pin out for the harness is as follows: Ø> DB 15 M TO/Pin# Description Ø> Pin # >1 RFG 0 - P 1 -1 +24 v 1. 3 A/0. 6 A >2 RFG 0 - P 1 -2 Common >3 RFG 1 - P 1 -1 +24 v 0. 6 A/0. 4 A >4 RFG 1 - P 1 -2 Common > 10 RFG 0 - J 3 -1 Alarm > 11 RFG 0 - J 3 -2 Alarm > 12 RFG 1 - J 3 -1 Alarm > 13 RFG 1 - J 3 -2 Alarm > > A second interface cable ties the RB to the XO as follows: Ø> RBJ 5 XOJ 5 Ø> Pin # Pin# Ø> 1 5 Ø> 3 3 > > The male DB 9 is P 1 and pin 1 = +24 v @ 400 ma, Pin 2 = Common. This will power > up the board so you can verify operation of the OCXO. Unfortunately that is > all the information I have on the unit. WA 5 JAT 20

Microwave Frequency Standard W 5 HN Internet Search Also Came Up with: Repair of Rubidium Source North Texas NTMS Microwave Society Author, G Molenkamp, ( vk 3 fgjm@commtelns. com) WA 5 JAT 21

Microwave Frequency Standard W 5 HN Repair of Rubidium Source-Cont’d WA 5 JAT North Texas NTMS Microwave Society 22

Microwave Frequency Standard W 5 HN Repair of Rubidium Source-Cont’d WA 5 JAT North Texas NTMS Microwave Society 23