D1 Mini ESP8266 Not Powering from GPS Module PCB – Voltage Drop Issue

HiBeing a lover of clocks and fascinated by time in Feb 2018 I was pleased to build the GPS Synchronised Analogue Clock Driver.  Unfortunately it never really lived up to my expectations although the clock did leap into action and set the correct time but after a while stopped and always struggled to receive signals even when left in the garden.  I did buy 2 of the PCB's but stopped construction of the second due to the poor results.

So I was delighted in the April 2019 when I saw an alternative 'Time Source' for the project and so returned to the project re energised with expectation.  But alas the power from the GPS Module PCB seemed insufficient to drive the D1 Mini ESP8266 module.  I decided to investigate and discovered although the module worked perfectly well when given a direct 3V supply but on connection from the Vcc and Ground  it failed to run with the voltage dropping to 1.8V across the D1.
I investigated this and found that although my 2 PCB boards were both 04202171 REV C they were not the same!  The resistor connected to the base of the transistor Q2 is printed as different values i.e. 4.7K on the one that I completed and 270 Ohms on the uncompleted board.
Could anyone offer any guidance as to which is the correct value  and/or and advice as to why the D1 mini is not receiving sufficient power to drive it and if the two facts may be connected.
I attached the 2 boards together the resistor values in question being just to the right of the inductor.  also shown are the diagrams from the original project.
any help greatly appreciated.alan

The original Silicon Chip article explains that the base drive via 270 ohm resistor is more than sufficient to supply the  regulator. If that is not working check the orientation of the transistor or try a new one. The 4K7 resistor is probably a carry over from the earlier version which used a darlington transistor as also explained in the article.
This link may help, I think it is for an earlier version of the same project.http://geoffg.net/GPS_Synchronised_Clock.html

Bill

Q2 is a saturated switch. When the base is high Q2 is off, and REG1 will not provide power.When the base is pulled low, REG1 will operate. REG1 is rated  to supply 200-300mA, depending on the output voltage, so the collector current will be about the same. Assuming a  minimum gain of 100 for Q2, the base current will be around 3mA (max). If the base is at ground, then the voltage drop across 4K7 is 3mA*4700 ohms, which takes Q2 out of saturation. At 270 ohms, this is not the case. This assumes that the minimum beta is 100, it is probably quite a bit higher. Additionally, it assumes a 300mA draw. Therefore 270 Ohms is a better bet if the spread of beta on  transistor  Q2 takes it down near 100 and the SMPS REG1 is supplying its maximum current.What is the current draw on the module when operating (worst case, with the tranceiver on). If it is over 200-300mA, then the SMPS REG1 will not be able to supply sufficient current and the voltage will sag. If you can't find the data, put the module on a metered supply and see what the current draw is.One question, a GPS module is designed to provide time, how are you using the ESP module to do the same, I take it an NTP server or the like. Note that the code on the PIC is designed to work with the original GPS module, your ESP module would need to work exactly the same way, or you will need to re-write the code and re-flash the PIC.Cheers,Richard