apolLO I kitting in progress …

We’ve received a number of orders for apolLO I programmable synthesizers so we had to enlist Katie’s help to get them all put together.  Here she is after the kitting carrying a stack of the apolLO I box #2 with the synthesizer and most of the ICs.

Katie carries a boxs for apolLO I synthesizer kits

Katie carries boxes for apolLO I synthesizer kits


Updated apolLO I Driver

The original apolLO I driver was built several years ago and only had support for 32-bit operating systems and has not been tested to any extent on Vista.  We have recently added 64-bit support and support for Vista with a new driver for the apolLO I USB-programmable oscillator.  This driver should download automatically if you are connected to the Internet.  If you are not being prompted to update your driver, you may also manually download it here as a ZIP file or here as an ISO file.

apolLO I Software Update

I have recently seen two situations where an apolLO I fails to lock, but does not appear to have a hardware issue.  Upon investigation, I discovered that the EEPROM where the setup is stored (frequency, etc) has been overwritten in the first location.  Specifically it has a 0xFF instead of an 0x23 in it.  I am not currently check-summing the values or performing any other checks and so it causes bad data to get loaded into the synthesizer.  This occurs for firmware 1.15 and earlier.  I have updated the software to check to ensure that if a 0xFF is found, it is replaced with a valid 0x23.  This is a temporary fix until I can find the root of the problem

I have not seen any other cases of this, but this could be because others assume they have damaged the board, etc.  If you have a no-lock situation when you believe it should be locking and have made sure that it is not your 10MHz reference and a valid frequency/PFD (R and N) are in the board and would like to check for this problem, you have a couple of options:

1) If you have access to a Microchip programmer, you can check the first EEPROM location (0) and verify that it has a valid value.  If it does not, you can reset the board to a factory state by writing 23 0D 70 04 00 00 00 0A 00 00 00 40 into the EEPROM starting at location (0).  Be sure to read the entire program, view the EEPROM, update it and then perform a program.  If you do not read the entire contents of the part first, you can write an empty program back into the part!

2) You can return to board to us and we will rewrite both the EEPROM and the updated software into the part and return the board to you.

If you have any questions, please feel free to drop me an email.  Note that the apolLO-32 does not use the EEPROM and therefore cannot have this problem.  All values are hard-coded in the software in the apolLO-32.


apolLO I Rev B SJ3 and SJ4 jumpers

The newest apolLO I boards have two new jumpers on them, SJ3 and SJ4, which have not made it into the documentation yet.  I’ve received a few questions about these and wanted to explain their purpose.

SJ3 should be fairly self-explanatory — it is marked as EXTREF and TCXO so that you can select between an on-board TCXO and an external 10MHz reference.  Just jumper the center to the marked side for where your 10MHz (or other 2-26MHz reference) lives.

SJ4 allows the output to be shifted from the RF synthesizers in the Si41x3 to the IF synthesizer.  I have not yet implemented the IF synthesizer in software, but I am working on this so this run of boards has this as an option.  Connect the center to the (H) side for RF use (700-1700MHz) or to the (L) side for IF use (62-1000 MHz).  Again, at the time of this writing, the software only supports the RF side so jumper to (H).