Experimental Baofeng RD-5R version

da3020
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Re: Experimental Baofeng RD-5R version

Post by da3020 » Tue Nov 10, 2020 7:57 am

ve7mdt wrote:
Tue Nov 10, 2020 7:12 am
... RD-5R is a viable option for you
Thanks alot.


Also, DL1DBY, how did You measure BER? Are any improvised ways?
R3EDC

DL1DBY
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Location: Frankfurt/Germany

Re: Experimental Baofeng RD-5R version

Post by DL1DBY » Tue Nov 10, 2020 12:28 pm

da3020 wrote:
Mon Nov 09, 2020 11:23 pm
I can't decide what to buy. I have an experience with OpenGD dm-1801 and I like it but it looks too big for me. I often wear station on my shirt pocket an 5R is much smaller but I care about usability and functionalyty. Is it mostly the same OpenGD for those two stations? (soldering of transistors doesn't scare me). Give advice, please!

Having bought 3 units of the RD-5R will only one working as it should I would strongly advise against buying an RD-5R. Even though it is small and cheap and nice with the OpenGD77 firmware.

DL1DBY
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Re: Experimental Baofeng RD-5R version

Post by DL1DBY » Tue Nov 10, 2020 12:31 pm

da3020 wrote:
Tue Nov 10, 2020 7:57 am
ve7mdt wrote:
Tue Nov 10, 2020 7:12 am
... RD-5R is a viable option for you
Thanks alot.


Also, DL1DBY, how did You measure BER? Are any improvised ways?
I am using a MMDVM duplex hotspot with Pi-Star which shows the BER. Big repeaters seem to have automatic adjustments for radios that are slightly off-frequency. The MMDVM does not do any adjustments of this kind which is not so good generally but useful in this case.
Last edited by DL1DBY on Tue Nov 10, 2020 12:40 pm, edited 1 time in total.

DL1DBY
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Re: Experimental Baofeng RD-5R version

Post by DL1DBY » Tue Nov 10, 2020 12:39 pm

VK3KYY wrote:
Mon Nov 09, 2020 8:33 pm
DL1DBY wrote:
Mon Nov 09, 2020 4:40 pm
I just managed to repair one of my bad RD-5R. It went from BER 13.7% to BER 0.3% and no more reboots with high audio volume. The radio had bad solder connections on the power transistor module (marked as H0606E JC1728, middle pin) and on the audio amplifier chip (marked as TDA2822, Pin 8 ground). I just resoldered these connections. :D
That's interesting to know.

Thanks for posting.
I now also resoldered ALL the pins of the power transistor module (marked as H0606E JC1728) and of the 4-pin module next to it (of unknown function, driver?, no markings on it). Though all of the SMD parts were machine-soldered in it was obviousy worse than soldering by hand. For this reason in faulty units all other solder joints should be visually checked, especially ground connections. Use flux when resoldering and remove flux afterwards.

da3020
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Re: Experimental Baofeng RD-5R version

Post by da3020 » Tue Nov 10, 2020 5:01 pm

DL1DBY wrote:
Tue Nov 10, 2020 12:39 pm
I now also resoldered ALL the pins...
Did it helps?
R3EDC

VK3KYY
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Re: Experimental Baofeng RD-5R version

Post by VK3KYY » Tue Nov 10, 2020 7:38 pm

The RF and other hardware in this nradio is much worse than the GD77 or the DM1801

The GD77 has separate Tx and RX sections for VHF and for UHF. The RD5R just has one wide band RF section for 100Mhz to 600MHz, with a low quality switchable output filter for UHF.
The spectrum analysis of the RD5R show its RF output is not clean

Its internal voltage regulator is too small and the voltage on the internal bus varies so much that the keypad LEDs flicker a lot when transmitting on DMR.

It also does not have a power management IC, so the software can't turn off the radio if the battery goes flat, and this will damage the battery.

Also, because it does not have a power management chip, the settings need to be constantly saved to EEPROM, whenever the frequency or mode etc is changed. Which slows the radio down and will eventually wear out the EEPROM

I would not recommend this radio.

Buy a GD77 , or perhaps a DM1801. But the GD77 is definitely the best radio

da3020
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Re: Experimental Baofeng RD-5R version

Post by da3020 » Sun Nov 15, 2020 1:36 pm

I have tried DM-5R Plus 2018 (with white screenlight) and it even won't work with frequency shift in DMR. H-version is 1.0.3.

So i don't want more experiments with DM-5R.

The question: are any significant hardware differences between Radioddity and 1801 radios?
R3EDC

VK3KYY
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Re: Experimental Baofeng RD-5R version

Post by VK3KYY » Sun Nov 15, 2020 10:49 pm

da3020 wrote:
Sun Nov 15, 2020 1:36 pm
I have tried DM-5R Plus 2018 (with white screenlight) and it even won't work with frequency shift in DMR. H-version is 1.0.3.

So i don't want more experiments with DM-5R.

The question: are any significant hardware differences between Radioddity and 1801 radios?
Yes.

The radio hardware is significantly different from the DM1801 and the GD77

Its not physically possible to put all the hardware from the DM1801 into the size of the RD5R

oh1fss
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Re: Experimental Baofeng RD-5R version

Post by oh1fss » Wed Nov 18, 2020 3:54 pm

VK3KYY wrote:
Tue Nov 10, 2020 7:38 pm
Also, because it does not have a power management chip, the settings need to be constantly saved to EEPROM, whenever the frequency or mode etc is changed. Which slows the radio down and will eventually wear out the EEPROM
Would it be possible to disable saving settings automatically to EEPROM for RD5R? And add a function to save settings manually instead?

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F1RMB
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Re: Experimental Baofeng RD-5R version

Post by F1RMB » Wed Nov 18, 2020 3:57 pm

Hi,
oh1fss wrote:
Wed Nov 18, 2020 3:54 pm
VK3KYY wrote:
Tue Nov 10, 2020 7:38 pm
Also, because it does not have a power management chip, the settings need to be constantly saved to EEPROM, whenever the frequency or mode etc is changed. Which slows the radio down and will eventually wear out the EEPROM
Would it be possible to disable saving settings automatically to EEPROM for RD5R? And add a function to save settings manually instead?
This is pointless and user unfriendly.
But the settings are not written all the time, they are written when they change, and this is managed with a bit of smartness to save the EEPROM write cycles count.


Cheers.
---
Daniel
73 de Daniel.

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