Output Attenuator - Revision history

G8GKQ: /* Attenuator Types */

2023-09-09T14:12:25Z

Attenuator Types

G8GKQ: /* Data Connections to the Raspberry PI */

2020-04-10T20:12:14Z

Data Connections to the Raspberry PI

M0YDH: /* RF Connections */ or Lime SDR

2019-01-31T18:42:15Z

RF Connections: or Lime SDR

G8GKQ at 08:31, 23 August 2018

2018-08-23T08:31:48Z

G4FRE at 19:47, 3 July 2018

2018-07-03T19:47:00Z

M0DHP: /* Introduction */

2018-02-15T17:43:45Z

Introduction

M0DHP: /* Preparation */

2018-01-12T17:42:36Z

Preparation

M0DHP: /* Preparation */

2018-01-12T17:41:17Z

Preparation

M0DHP: /* Data Connections to the Raspberry PI */

2018-01-12T17:38:52Z

Data Connections to the Raspberry PI

M0DHP: /* Attenuator Types */

2018-01-12T17:35:52Z

Attenuator Types

@@ Line 10: / Line 10: @@
 Data sheets are available at these links:
-  http://www.psemi.com/pdf/datasheets/pe4302ds.pdf
+  http://www.psemi.com/pdf/datasheets/pe4312ds.pdf
-  http://www.psemi.com/pdf/datasheets/pe43703ds.pdf
+  https://www.psemi.com/pdf/datasheets/pe43713ds.pdf
   http://www.analog.com/media/en/technical-documentation/data-sheets/HMC1119.pdf.

@@ Line 42: / Line 42: @@
 The attenuator shares the clock and data lines used by the ADF4351 synthesizer.  A separate LE line is used, connected to Pin 10 of the GPIO connector.  This pin can be accessed from the "DigiThin" connector on the Portsdown GPIO board.
-During testing of the PE43703, it has been found that connecting the attenuator board can cause the ADF4351 to fail to start; the ADF4351 seems to be particularly fussy about the rise times on its programming signals.  To overcome this problem, and to prevent any possible damage to the Raspberry Pi from the +5v present on the attenuator board, it is recommended that the 3 signal lines to the attenuator are connected through 1K resistors.  The connections are as follows:
+During testing of the PE43703, it has been found that connecting the attenuator board can cause the ADF4351 to fail to start; the ADF4351 seems to be particularly fussy about the rise times on its programming signals.  To overcome this problem, and to prevent any possible damage to the Raspberry Pi from the +5v present on the attenuator board, it is recommended that the 3 signal lines to the attenuator are connected through 1K resistors.  The connections are as follows (use the physical pin numbers):
 {| class="wikitable"
 |-
-! Signal !! GPIO Pin !! Notes
+! Signal !! GPIO Physical Pin !! BCM No !! Wiring Pi !! Notes
 |-
-| LE || 10 || through 1K from DigiThin Connector
+| LE || 10 || 15 || 16 || through 1K from DigiThin Connector
 |-
-| CLK || 29 || through 1K from ADF4351 CLK
+| CLK || 29 || 5 || 21 || through 1K from ADF4351 CLK
 |-
-| DATA || 31 || through 1K from ADF4351 DATA
+| DATA || 31 || 6 || 22 || through 1K from ADF4351 DATA
 |}

@@ Line 56: / Line 56: @@
 ===RF Connections===
-The attenuator should be wired between the RF output of the Filter-modulator board and the input to the 4-way (or 8-way) switch.  That way it will be in-circuit on all bands.  The attenuator level can be set and stored for each band independently for use with the Portsdown DATV transmitter.
+The attenuator should be wired between the RF output of the Filter-modulator board [or Lime SDR] and the input to the 4-way (or 8-way) switch.  That way it will be in-circuit on all bands.  The attenuator level can be set and stored for each band independently for use with the Portsdown DATV transmitter.
 It could also be placed directly on the second output of the ADF4351, and the signal generator software allows for this.  However, this is for a direct output, and will not work as a means of altering the output level from the Portsdown filter-modulator.

@@ Line 1: / Line 1: @@
 ===Introduction===
-It is possible to add a programmable output level attenuator to the Portsdown transmitter.  As of software version 201802041, the output attenuator can be used to adjust the output level of the Portsdown Signal Generator and allows programmable output levels to be set for each band and additional transverter outputs.
+It is possible to add a programmable output level attenuator to the Portsdown transmitter.  The output attenuator can be used to adjust the output level of the Portsdown Transmitter and Signal Generator and allows programmable output levels to be set for each band and additional transverter outputs.
 ===Attenuator Types===
@@ Line 56: / Line 56: @@
 ===RF Connections===
-The attenuator should be wired between the RF output of the Filter-modulator board and the input to the 4-way switch.  That way it will be in-circuit on all bands.  Note that it should only be put in-circuit for use with the signal generator at present. a further software update is required before it can be used with the Portsdown DATV transmitter.
+The attenuator should be wired between the RF output of the Filter-modulator board and the input to the 4-way (or 8-way) switch.  That way it will be in-circuit on all bands.  The attenuator level can be set and stored for each band independently for use with the Portsdown DATV transmitter.
 It could also be placed directly on the second output of the ADF4351, and the signal generator software allows for this.  However, this is for a direct output, and will not work as a means of altering the output level from the Portsdown filter-modulator.

@@ Line 5: / Line 5: @@
 ===Attenuator Types===
-Attenuators based on the PE4302, PE4312, HMC1119, PE43703 or PE43713 are supported.  The PE4302 and PE43703 types are readily available on eBay for under £20.  The preferred type is the PE43703 illustrated here with its screening cover removed:
+Attenuators based on the PE4302, PE4312, HMC1119, PE43703 or PE43713 are supported.  The PE4302, PE4312 and PE43703 types are readily available on eBay for under £20.  The preferred type is the PE43703 illustrated here with its screening cover removed:
 [[File:PE43703 post-mod small.jpg|480px]]
@@ Line 33: / Line 33: @@
 The PE4302 uses the same three signal lines as the PE43703.  Details of how to configure the board for serial control can be found here: https://wiki.batc.org.uk/PE4302
 ===Data Connections to the Raspberry PI===

@@ Line 16: / Line 16: @@
 ===Preparation===
-As supplied, the eBay pre-built attenuator boards are generally configured for control by DIP switches, not by a Raspberry Pi.  '''NOTE THAT IF CONNECTED WITHOUT MODIFICATION THEY MAY KILL YOUR RASPBERRY PI!'''  The modification details for one of the PE43703 boards are detailed here - your board may differ!  Please could a PE4302 owner publish similar information??
+As supplied, the eBay pre-built attenuator boards are generally configured for control by DIP switches, not by a Raspberry Pi.  '''NOTE THAT IF CONNECTED WITHOUT MODIFICATION THEY MAY KILL YOUR RASPBERRY PI!'''
 There are 3 signal lines used to program the PE43703: LE (Latch Enable), CLK (Clock) and Data.  For DIP switch programming the LE line is connected to +5v.  This line needs to be disconnected from +5v otherwise it will try to put 5v on a 3.3v RPi GPIO output.  Referring to the picture below (pre-modification):
@@ Line 29: / Line 31: @@
 ====PE4302====
 ===Data Connections to the Raspberry PI===

← Older revision		Revision as of 17:41, 12 January 2018
Line 27:		Line 27:

	Apply power (5v) to the unit. If all is well, the power LED should light; if not, recheck J4. Then check the voltage on the DATA, CLK and LE pins. They should all be at 0v. Using a 1K resistor, check that each of them can be pulled up to 5v. Only after these checks is it safe to start making connections to the RPi.		Apply power (5v) to the unit. If all is well, the power LED should light; if not, recheck J4. Then check the voltage on the DATA, CLK and LE pins. They should all be at 0v. Using a 1K resistor, check that each of them can be pulled up to 5v. Only after these checks is it safe to start making connections to the RPi.
		+
		+	====PE4302====

	===Data Connections to the Raspberry PI===		===Data Connections to the Raspberry PI===