Delta Pulse - Take 2

[MDfanatic]

Someone made a colossal mistake

[arthur1974]

Hi folks,

I'm currently in the process of ordering the components for my Delta Pulse Legend REV 5.0 in order to assemble it. The following deviations are planned so far:
1. mount all ICS on sockets (for better repairability)
2. according to the BOM, C1, C4, C5 as well as R1 and R7 are to be changed in valvue for small coils. I would make these components pluggable with pin headers in order to be able to change to large coils without soldering if necessary. For a future REV 6.0 board, these components could be made pluggable with a jumper in the layout.

Are there any other pitfalls when setting up the board?

Thanks and cheers,
Arthur

[kt315]

mount all ICS on sockets (for better repairability) does give nothing. you just add an amount of unreliable connections.
in my experience there were people, them was much, who had problem with sound on NE555, at last stage. yes, it was just the socket.
while NE555 stage is very simplest circuit, for them it was THE GRANITE WALL they were not able to throw go.
then i did TWO videos with the checking the sound to show. this is really discouraged me

[MDfanatic]

arthur1974 if you own a hot air station, you should solder the IC straight to the PCB.

If you don't have a hot air station and you use the sockets, triple check that the IC is correctly seated to the socket as kt315/suggested.

[kt315]

1. for checking of all kind op amps i released a tester. it also checks comparators. but geotechers are still in dark room. they do not undestand what i do for them.
2. for checking of NE555 i did suggest to buy simplest kit from aliexpress. them much there. i gave links. its price cents. zero reaction.
3. for checking of all components i did suggest to buy kit of TRANSISTOR TESTER, its very popular. i did create an album and put its pics, i told in microdetails about this tester. but geotechers again are in the dark room.

[MDfanatic]

Why would you buy electronics from eBay?

Unless you want to play Russian roulette with your money, time and patience.

Just buy from LCSC.com and you will not need to test anything.

[kt315]

opamp comparator tester - Geotech Forums (geotech1.com)

User Profile - Geotech Forums (geotech1.com)

UPD. second link is not working, a bug of the forum. try

[arthur1974]

OK, I'll leave out the sockets, have to check the sound videos on YT from KT315. I'm going to buy an OP AMP tester, which is actually still missing from my workshop equipment. I don't have a hot air soldering station, but I do have a good soldering station from Weller and solder with a low solidus temperature. Many thanks for all the good advices!

[kt315]

good reading Chinese toys - Geotech Forums (geotech1.com)

[arthur1974]

Hi,
In the BOM I read the following information:

If you want to use Delta Pulse with just small coil.
Q: How small is small? D < 25 cm?

You can tune FIRST DELAY to its minimal value 12-15us.
Change C4 to 820-910pF. R7 to 7.5k.
Change C5 to 1nF to decrease STROBES' WIDTH to 20-25us.
Q:
FIRST DELAY: change C4 + R7?
STROBES WIDTH: C5?

Tune frequency to 300pps. Change C1 to 10nF and R1 to 160-180k.
Q: For small coils must ALL (C1, C4, C5, R1 R7) the above changes be made?

Thanks, Arthur!

[kt315]

I took the data from the forum... but i do not recommend to do this changes on your first step because headache.
get 'classic' DP, check it in a field, after 1 year of the hunting you can mod something.
i had got huge stream of laments on very unstable work on the ground from guys doing those mods. could help them nothing.
if you want to get PI working with small coils look on a side of HH, Bara, Minipulse etc projects.

small coil is just for checking/tuning in your room. you can NOT check 1x1 meter coil in VERY hard conditions of your home/house.

pleasure

[kt315]

GUYS,

I GIVE AN ACCESS TO THE ARCHIVE HANDY. IF SEE A REQUEST. I DO NOT SIT NEAR PC WHOLE DAY. BE PATIENCE AND WAIT.
ESPECCIALY IF YOUR SUN IS VERY HOT THERE.

[Emersonpaz]

I have all the original values of C4,C5,C6-1.5nf R7-15k, R8-27k and R9-68k and I am reading on the oscilloscope T4 and T5 15us and it should be 45us. can anybody help me?

[kt315]

again strange working 4538. change them on another type.

in BOM file you must see a line

DD1 4538 HEF4538BP, 74HC4538N, MC14538BCP
do not use CD4538 (RCA)

[Emersonpaz]

Yes, I'm using the CD4538BE, I'll try to get other ci's to test. Thank you kt315.