Ensemble RX II 03_Local Oscillator and Control

Install Protective Topside Parts

Install these resistors first, so as to protet against solder splashover at pins 4 and 8 off the Si570 (see below)

Check	Designation	Component	Marking	Category	Orientation	Notes
❏	R07	2.2k 1/6W 5%	red-red-red-gld	1/6W	N-S
❏	R08	2.2k 1/6W 5%	red-red-red-gld	1/6W	N-S

Install Bottomside Components

Watch out when installing C35 to avoid solder splashover into the adjacent holes for the T1 primary windings.

Note the orientation photo for the Si570 and install with correct orientation.

Pay close attention to the pins 4 , 7, and 8, as their footprint is quite small relative to the other pads. The very tight space around those pins and the multiple contacts in close proximity can easily lead to frustrating solder bridges.

Check	Designation	Component	Marking	Category	Orientation	Notes
❏	U03	Si570 Programmable Oscillator	SiLabs 570	I2C		Take ESD precautions
❏	C30	0.1 uF	(smt) black stripe	SMT 1206	white pads
❏	C33	0.1 uF	(smt) black stripe	SMT 1206	white pads
❏	C35	0.1 uF	(smt) black stripe	SMT 1206	white pads

Wind and Install T1

You should take two 5" strands of #30 wire and twist them together ("bifilar") so you get around 3 twists to the inch. Using the resultant bifilar strand, thread it through the binocular core for two turns. Remember a turn is a trip that:
(1) starts at a particular hole
(2) goes into that hole and out of the other end
(3) goes into the hole nthat is across from the hole out of which it just exited, and
(4) Comes out of the hole at the opposite end and across from the original entry hole.
Do that series twice with the twisted pair and you have a transformer with two windings (each winding corresponding to one of the two twisted single wires).
Each winding (primary and secondary) is two turns. Since the windings are identical in length and number of turns, you can arbitratily pick either one as the primary, with the remaining winding serving as the secondary winding.
(Hint: use an ohmmeter (or other continuity checker) to identify which wire-ends go together to make the ends of a winding.

ALERT: The pcb layout for the Ensemble RX II has incorrect placement of the ground holes for the windings of T1, the local oscillator isolation transformer. This will be rectified in a later version of the pcb (as of 19 Juy 2012, the original version is documented herein).
If the local oscillator isolation transformer is not connected properly some of the Si570 fundamental and harmonics will be radiated from the USB and other cables.
The principle is that the grounded side of the isolation transformers should go to the same end of the primary and secondary. The two wires that come from the same hole in the binocular core.
The fix for this is documented in a paper by Alan G4ZFQ - please refer to that paper for the important details.

If you are unfamiliar with winding and installing inductors, you may want to refer to the WB5RVZ construction hints for coils (toroidal) and transformers ( toroidal and binocular). Click here for details on identifying toroid cores.

Decoding the trqansformer specifications:

Transformers' windings are specified using the pattern "nnT/wXmmT" or "wXmmT/nnT", where:

• "nn" is the number of turns in the single winding
• "mm" is the number of turns in the multiple windings
• "w" = the number of multiple windings (e.g., 2 = bifilar; 3 = trifilar, etc.)

Thus, e.g., "18T/2x9T bifilar #30" means, using #30 wire, produce a single 18 turn primary winding and two 9-turn secondary windings; "2x9T bifilar/ 18T #30" means, using #30 wire, produce two 9-turn primary windings and a single 18 turn secondary winding.

Check	Designation	Component	Marking	Category	Orientation	Notes
❏	magwire	Magnetic Wire, enameled #30		Magnetic		(total of 30 ft. provided in kit)
❏	T01	band-specific	Band Component Marking HF 5.76uH: 2T(bi)T #30(8 (2x4)in) on BN43-2402 (xfrmr) LF 12.96uH: 3T(bi)T #30(10 (2x5)in) on BN43-2402 (xfrmr)	misc		change from 3Ttrifilar

Install Topside Ics

Double check the orientation on the two optoisolators. They should be oriented so that their "dimple" is in the upper left-hand corner.

Check	Designation	Component	Marking	Category	Orientation	Notes
❏	SO1	8 pin dip socket		Socket		for ATTiny85
❏	U01	ATtiny 85-20 PU w/V15.12 Firmware	AVR ATTINY85-20PU	DIP 8	(dimple in upper right)	Take ESD precautions
❏	U04	LTV-817 Opto-Isolator	LTV 817	DIP-4	(dimple in upper left)	Take ESD precautions
❏	U05	LTV-817 Opto-Isolator	LTV 817	DIP-4	(dimple in upper left)	Take ESD precautions

Install Remainder of Topside Components

Careful installing the resistors and diodes clustered near the USB connector area. Builders have been known to insert these into the wrong holes. Review the board layout and the orientation column below to double check the orientation.

The body of each zener is to be located above the silkscreen circles for D1 and D2 on the board with the diodes mounted standing perpendicular to the board in a hairpin fashion. The banded end of each diode is then at the lead of the diode that loops back to the circuit board.

Check	Designation	Component	Marking	Category	Orientation	Notes
❏	D1	BZX55C3V3 3.3V zener diode	BZX55C	Axial		The band end of the diode is the hairpin lead - see board layout
❏	D2	BZX55C3V3 3.3V zener diode	BZX55C	Axial		The band end of the diode is the hairpin lead - see board layout
❏	C03	0.01 uF	103	Ceramic	horiz
❏	R01	68 1/6W 5%	bl-gry-blk-gld	1/6W	N-S
❏	R02	68 1/6W 5%	bl-gry-blk-gld	1/6W	N-S
❏	R03	2.2k 1/6W 5%	red-red-red-gld	1/6W	E-W
❏	R05	2.2k 1/6W 5%	red-red-red-gld	1/6W	W-E
❏	R06	2.2k 1/6W 5%	red-red-red-gld	1/6W	W-E
❏	R09	2.2k 1/6W 5%	red-red-red-gld	1/6W	W-E	chenged from 221
❏	R12	10 k 1/6W 5%	brn-blk-ora-gld	1/6W	N-S
❏	R13	10 k 1/6W 5%	brn-blk-ora-gld	1/6W	N-S
❏	R04	1 M 1/6W 5%	brn-blk-grn-gld	1/6W	E-W

Download and Install Required Software

All of the latest versions of essential firmware configuration programs, USB driver and their associated documentation can be obtained from Fred PE0FKO's website:

• USB driver: (search for "Download Firmware source and .hex files")
• CFGSR program: (search for "Download")
• Documentation

In order to test (and later, operate) your rig, you must download and install required software (SDR programs and Dynamic Link Libraries, along with hardware drivers. The actual steps and programs may vary, depending upon your computer's windows operating system version (XP, Vista, or Windows 7) and architecture CPU/memory (32 bit or 64 bit).

The following links are provided and, as of 7/8/2010, are current:

Note: Rocky latest version is 3.6. Operates fine on Windows XP; in later Windows versions, Rocky will operate, but only recognizes USB soundcards. Has RXTX for CW and PSK31; RX only for SSB.

^*Note on installing PE0-FKO's USB Drivers: Fred's website has an excellent step-by-step guide to instaling the USB driver.

Install Driver

The correct procedure is to download the driver and put it in a suitable folder, then plug in the USB lead, Windows should detect new hardware has been found and you need to manually point it to the folder containing the drive. It should then install correctly. Certainly does on Win2000 and XP. On Vista or Windows 7, there used to be some issues with driver signing. There have been messages on the forum describing methods of working around these issues. One such solution is addressed in the author's MOBO4.3 builders notes.

LibUSB - "Unknown Device" Error

Others have experienced the dreaded "Unknown Device" problem upon plugging in the USB cable after having installed the LibUsb driver. This "unknown device" problem (and a remedy for those who are using Logitech cordless mouse and/or various wireless internet connection adaptors) are discussed in message #45071 and Message #47755 on the Yahoo Softrock40 Group

Install/Run CFGSR ("ConFiGureSoftRock")

Once the driver is installed, if you run 'CFGSR' that will either automatically 'open' the firmware, or if not, you need to go to the 'USB' tab and select it from the list displayed in the bottom box. Which way depends on if you have 'CFGSR' set up to auto connect on program start or not.

For further discussions of the software side of SDR and soundcard issues, see Alan G4ZFQ's pages.

Test Local Oscillator

You can use 'CFGSR' to exercise the Si570 using the 'Tune' tab that makes it into a 'VFO'. Just a case of setting the frequency, and the Si570 should output a signal at 4 times the frequency displayed on the main display on the screen. The 'Test' tab can also be used to look at all the various Si570 registers etc, but probably unnecessary as if you can hear or measure the Si570 output frequency, you know it is working.

Configure Si570 for LF Option

For the LF version, it will be essential to change the firmware configuration to successfully operate that version. Tthe default values are only suitable for the 'normal' HF version.

Changes needed are (using CFGSR.exe):

• Si570 tab

  set the minimum device frequency to 3MHz (default 6MHz). Although the Si570 will not run below 3.5MHz, the box only accepts integer values

• LO tab

  need to change the 'LO:Total' multiply for bands 0 - 3 from the default x4 to x16

• ABPF tab

  need to change the filter cross over points to 0.4, 0.8 and 1.6MHz

(TX to Bob G8VOI for the instructions on how to configure the Ensemble RX II Local Oscilklator for LF operation.)