Tesoro Lobo news

[bernte_one]

hello

looks good many thanks
maybe it is the first double sided pcb i will do.

regards from germany, bernd

[Legaucho]

Hello bernd,

You have to check some values, I already do a simple PCB that works but discrimination is low.
Here are some links on this topic LOBO:

http://redram.0pk.ru/viewtopic.php?id=23&p=3

http://redram.com.ua/sam/lobo.html

http://md4u.ru/forum/viewtopic.php?t...=asc&start=125

NOTE: I put two terminals on TX and RX that you can adjust the different values of the capacitors chosen in function of the kind of searchcoil.

Good luck

[Legaucho]

Hey bernd,

I find a little mistake this morning, and I have by the same opportunity the answer to my problem.

See my two attached pictures

[amtech2005]

Hello Legaucho . The pcb looks good to me , I was just wondering about the zero resistor ?

It seems this Lobo is starting to become a very popular project , especially on Russian forums too . After the tiny bugs are worked out , it will be a great machine !!

Regards..........Eugene

[Legaucho]

Hello Eugene

In the original Lobo PCB there are several Resistor with 0 Ohms using like bridge.

Best regards

[amtech2005]

I see that now , I wonder why Tesoro did that ? A fuse to burn ?

Also the 17.5 khz must work better in Europe or Russia maybe because of 50 cycle AC ?

I am finally ordering all the parts next week . Everything is easy to get except Lm308 is obsolete now.

Best Regards...............Eugene

[Qiaozhi]

I see that now , I wonder why Tesoro did that ? A fuse to burn ?

Also the 17.5 khz must work better in Europe or Russia maybe because of 50 cycle AC ?

I am finally ordering all the parts next week . Everything is easy to get except Lm308 is obsolete now.

Best Regards...............Eugene

Using zero ohm resistors is just another way of making the topside connections on a single-sided PCB, rather than using wire links.

[porkluvr]

Everything is easy to get except Lm308 is obsolete now.

That's bad news.

Alltronics has the LM308H for $2.95 and the metal can is supposed to be the best, quietest.

You can purchase on LM308N on ebay for about $1 each, although those are from asian vendors and possibly counterfeit - but at that price maybe worth the risk.

If money is no object, Linear Technology makes the LT1008. Buy direct for ~$4 (+shipping) or purchase from Digikey for $5.50 (+shipping).

[amtech2005]

In doing some cross reference research the TL070 or [TL071 possible] but what was mentioned was the external capacitor needed on substitutions to correct a bad "Slew Rate" of these chips ? How about OP07 ?
Nte938 is $10.00 bucks .

This LM308 problem was already discussed here on this forum .
The BF245 is cheap replacement but no metal can like original 2n3493.

BR...........Eugene

[homefire]

I listed the LM3080N on the parts list I sent but looking again I don't think so.

[amtech2005]

Homefire . OP07 looks like maybe ?? A very Good price @ one buck each !!!

AD797 = NO !!!!

HH........E.

[homefire]

Can pins 1 and 8 be left floating. No Off set control>

Brain Fart , Never mind.

[homefire]

All Electronics has them!

They only want a Arm and four Toes for them. LOL

But then Mouser wants $10.00 for the NTE Version. http://www.mouser.com/ProductDetail/...zjLdtelA%3d%3d

[homefire]

LM308N $5.33 here: http://store.americanmicrosemiconduc...FSUbQgodcEAS2w

[Legaucho]

Hello all,

There are two externals resistors on front plate potentiometers.