more pictures :
the box looks like printed on something - but is extremely well looking and durable and actually have a heavy feeling like metal…
I paid £32 for 2 - e.g. £16 each - I have a repeating order for this once as they fit perfectly to my needs ( I have 50+ ordered so far )
Re - 3D printed enclosure - yes that’s clear but to get quality enclosure is almost impossible for reasonable price - even with SLA printer in the end the enclose looks at best - acceptable - and also very expensive - with quality SLA 3D printing services I’ve pad about £12 only for the enclosure at it was still miles way from the one from aliexpress to be honest…
btw: my dream is someone to start producing enclosures that look great and do good job and reasonably priced with the proper openings 
- usually the enclosures are always the non-solvable problems in my little projects
not only yours 
but if compared to the expense to be incurred to start an injection print, perhaps there is no alternative for now
I have come to the following solutions so far :
pre-build dev board + enclosure -as the one in the pictures ( that is why I like it so much) - buit works generally only for gateways
print a 3D enclosure - usually looks awful or expensive and not durable …
buy a ready enclosure
-option 1 - buy a closest available box and use a laser engraver/cutter to cut the rectangular openings
correction of the pins for TTGO 2.1-1.6 proper one are :
// LORA
#define CS_PIN 18
#define RST_PIN 23
#define INT_PIN 26
#define LED_PIN 25
//.OLED
#define DISPLAY_ADDR 0x3c
#define DISPLAY_SDA 21
#define DISPLAY_SCL 22
#define DISPLAY_GEOMETRY GEOMETRY_128_64
#define DISPLAY_RESET_PIN 16
There appears to be a new Heltec ESP32 LoRa board:
New features (based on below specs / source):
Processor
Adopt Lexin’s ESP32 chip
LoRa
Using Semtech’s SX1276 chip
WiFi
Bluetooth
Bluetooth v4.2 full standard, including traditional Bluetooth (BR/EDR)
and Bluetooth Low Energy (BLE)
Human interaction
power supply
interface
storage
Power consumption
Mechanical structure
I checked the pin wirings for the new TTGO T-Fox and found these:
#define HAS_LED NOT_A_PIN // green on board LED is useless, because it's wired to GPIO25 = LORA_RST
//#define LED_ACTIVE_LOW 1 // Onboard LED is active when pin is LOW
#define HAS_BATTERY_PROBE ADC1_GPIO35_CHANNEL
#define BATT_FACTOR 2 // voltage divider 100k/100k on board
#define HAS_BUTTON GPIO_NUM_36 // on board button (next to reset)
// Pins for I2C interface of OLED Display
#define MY_OLED_SDA (21)
#define MY_OLED_SCL (22)
#define MY_OLED_RST U8X8_PIN_NONE
// Pins for on board DS3231 RTC chip
#define HAS_RTC MY_OLED_SDA, MY_OLED_SCL // SDA, SCL
// Pins for LORA chip SPI interface, reset line and interrupt lines
#define LORA_SCK (5)
#define LORA_CS (18)
#define LORA_MISO (19)
#define LORA_MOSI (27)
#define LORA_RST (25)
#define LORA_IRQ (26)
#define LORA_IO1 (33)
#define LORA_IO2 (32)
That means:
TTGO T-Fox running new paxcounter v1.7.12 which supports on board RTC chip Maxim DS3231 to keep time:
I found some additional details on my TTGO T-Fox board:
Powerswitch: GPIO25 controls a MOS-FET which switches power supply for LoRa-Chip (HPD13) and display. So for low power applications these components can be powered off and on by software.
This does not apply to the USB-UART chip (CP2104), it’s always powered and the suspend inputs are not wired to the CPU
LoRa-chip for the “27dBm” version is a HPD13AP, powered with 5V.
There is a solder bridge on the board to select power of LoRa chip: 3,3V or 5V
RTC chip DS3231 interrupt output line is wired to GPIO34, so can be used to wake up ESP32 from deep sleep by an alarm generated by the RTC chip.
RTC is powered with 3,3V when board runs on USB or battery power, and is powered by backup battery when board power goes off.
Battery power can be measured via a voltage divider (100k/100k) wired to GPIO35
The on board LED is connected to the power switching line and has active low logic, so is more or less useless (light on = power off / light off = power on)
So the T-Fox brings some new features to implement low power applications.
First, thank you all for those threads, they really help me out using those boards.
Can you check if the CP2104 is also powered (not suspended) when running on 3.3V from a LiPo?
I read somewhere, that the CP2104 in contrast to the CP2102 suspends when not being connected to D+/D-.
Ideally, could you check the power consumption in deep sleep?
A nice start but a missed opportunity if the UART and voltage divider cannot be switched off.
The UART chip and voltage divider probably draw (much) more current than the display in sleep and HPD13 in sleep/standby mode. The voltage divider alone at 3.7V draws 18.5 uA already.
Can you provide a sample code to run for deep sleep operation?
As far as i overlook it, the following components will contiously draw battery power, and cannot be controlled by software on ESP32:
Hello guys,
I made a small pcb to avoid the power consumption of my heltec v1. I used an attiny85 to control the power ON and OFF of my board, this way I achieved around 20uA in sleep mode (the deep sleep mode consumption from attiny).
Just using some transistor and the attiny85.
I hope it can helps someone =D
Prototype code (for TTGO LoRa v1) is available on GitHub: https://github.com/Nature40/Satellite-BatCave
maybe … if you have a link ? 
Battery control circuit:
Just replace the BC448 for one C32740
Attiny85 Code:
#include <avr/sleep.h>
#include <avr/wdt.h>
#ifndef cbi
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#endif
#ifndef sbi
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
#endif
int pinLed = 3;
volatile boolean f_wdt = 1;
void setup(){
pinMode(pinLed,OUTPUT);
// approximately 4 seconds sleep
//setup_watchdog(8);
}
void loop(){
if (f_wdt==1) { // wait for timed out watchdog / flag is set when a watchdog timeout occurs
f_wdt=0; // reset flag
digitalWrite(pinLed,HIGH); // let led blink
delay(2000);
digitalWrite(pinLed,LOW);
pinMode(pinLed,INPUT); // set all used port to intput to save power
// Parameter should be multiple of 8 and should be grater than 8
sleep_tiny(8);
//sleep_tiny_750();
pinMode(pinLed,OUTPUT); // set all ports into state before sleep
}
}
// set system into the sleep state
// system wakes up when wtchdog is timed out
void system_sleep() {
cbi(ADCSRA,ADEN); // switch Analog to Digitalconverter OFF
// setup_watchdog(8);;
set_sleep_mode(SLEEP_MODE_PWR_DOWN); // sleep mode is set here
sleep_enable();
sleep_mode(); // System sleeps here
sleep_disable(); // System continues execution here when watchdog timed out
sbi(ADCSRA,ADEN); // switch Analog to Digitalconverter ON
}
// 0=16ms, 1=32ms,2=64ms,3=128ms,4=250ms,5=500ms
// 6=1 sec,7=2 sec, 8=4 sec, 9= 8sec
void setup_watchdog(int ii) {
byte bb;
int ww;
if (ii > 9 ) ii=9;
bb=ii & 7;
if (ii > 7) bb|= (1<<5);
bb|= (1<<WDCE);
ww=bb;
MCUSR &= ~(1<<WDRF);
// start timed sequence
WDTCR |= (1<<WDCE) | (1<<WDE);
// set new watchdog timeout value
WDTCR = bb;
WDTCR |= _BV(WDIE);
}
// Watchdog Interrupt Service / is executed when watchdog timed out
ISR(WDT_vect) {
f_wdt=1; // set global flag
}
void sleep_tiny (int seconds){
int m = 8;
int t = seconds/m;
for (int i=0;i<t;i++){
setup_watchdog(m);
system_sleep();
}
}
void sleep_tiny_750 (){
for (int i=4;i<6;i++){
setup_watchdog(i);
system_sleep();
}
If you need anything else let me know!
Guys,
I really need a help with my esp heltec board. I have two main problems
1 - My receive node stops to work after a few minutes. I’m using LoRa.parsePacket();
2 - If I increase the message size ( like 15 bytes) it stops to receive, when I increase the message the receiver stops to work more often too.
Please can anyone help me with this? Im blocked for weeks. =/
Without link to the code running on your Heltec board there won’t be any answers possible here.
Hello Verkehrsrot,
Even with the OLED_LoRa_Receiver and OLED_LoRa_Sender examples I’m having this kind of problem.
Problem 1:
My receive just stops to receive, it’snt blocked, but LoRa.parsePacket() just return zero after a while, when a reset the module it start to receive again.
Problem 2:
For the size of the packet how many bytes is the maximum? I saw in the datasheet of SX1276 that we could send a packet with 256 bytes but Im not even close and the receive start to lose a lot of packages when the package has a size like 15 bytes.
Dou you guys think that it could be my board? How many bytes did u send whitout a considerable packet loss.