Tesoro Lobo news

[Derx]

All wire connecting same absolutely
Only text label turn up-down
How to choose?

[Derx]

What is correct tri-state switchs connect?
Version 1 left or version 2 right?

[Derx]

Hey.
You can specify how to simplify assembly of the two switches to one? Or delete all?
What is the frequency of the original instrument? Saw a few options, but what right - I do not know.
How to make 2-tone sound, all-metal and discrim chanell?

[herpes]

sorry, but I just saw the voltage regulator is also very rare lm 2930t -8, still have a l7808 can I replace this?
'm no electronics specialist

[porkluvr]

Hi, is there a substitute for ls204cb IC, same pin assignment?

MC33178 (same as used in Bandito)

[herpes]

okay, thank you

[shevakotik]

Hi, is there a substitute for ls204cb IC, same pin assignment?

NE5532, JRC4558

[herpes]

Hi, is there a substitute for ls204cb IC, same pin assignment?

[zoltan]

Ground Balance

Hello everyone!
Excuse me!
Then now the pictures.

[Qiaozhi]

Hi for everybody!
I write from Hungary.

II built it LOBO
LOBO works.

I cannot portray it correctly Ground balence.
Somebody can prepare a short video the correct one tuning.

Thank you

Zoltan - I had to remove your first post where you attempted to add an image. The image was added as an enormous amount of text that caused the page to load very very slowly, and nothing but many pages of text was displayed.

Please make attachments using the Manage Attachments button further down the page. You have to make at least one post before you can add attachments anyway, and you should now be able to do that. Also, please make careful note of the recommended image sizes.

[zoltan]

Ground Balance

Hi for everybody!
I write from Hungary.

II built it LOBO
LOBO works.

I cannot portray it correctly Ground balence.
Somebody can prepare a short video the correct one tuning.

Thank you

[porkluvr]

Zoomix, have you not even tried to determine why your L numbers and FOMA's L numbers are so different?

You should to understand that when the Lobo schematic first became available here, The coil parameters listed for Lobo in "Coil Data" were 100% backwards. I myself was duped into trying to simulate and verify a Lobo clone in LTspice, using the incorrect coil information. It finally dawned on me what I was doing was absurd but it took my twice contacting Admin before anything got changed on the web page, and 2~3 years had elapsed.

I think the Russians figured out quickly that our Coil data was wrong and started early on using 1.33mH for tx and ~11mH for rx, but their schematic notes would be in Russian (spank you very much). Also some posters here (not necessarily Russian) insisted on posting major modifications - of course most of those modifications came without any explanation, English, or otherwise. Really not much help, imho only adding to confusion. That's only my perspective, and my memory is not perfect.

So anyway some of those notes on Foma's drawing may be incorrect and I admit that I had a hand in that because I tried to interpret Foma's meaning - ummh, but I know absolutely no Russian, and I have not physically tested anything, but I made notes on his drawings and reposted them. Anyway, I have tried to correct known errors that I myself contributed, but I'm not perfect.

There may be some mistakes on the formulas for the coils on "Foma's" drawings. Possibly my bad, or possibly I only copied already incorrect information, I don't know.

But, instead of you running out and buying a coil from some other manufacturer, you could try to experiment with coil geometries and modifying number of turns until you get something close to the Lobo target values. I'd probably like to do that myself just to try and make real some contribution here, but I have one or two pressing projects already, and very little physical energy to tackle anything.

I have attempted several times to make my own PCB layout (but adapted to my own power supply needs) but always got either frustrated, or sidetracked, or thought better of it because of all the CONFUSION surrounding this little beastie.

[zoomix]

Hello polkruv,

I actually have a problem with the coils and it does not benefit the development of the lobo.

I have an original and SEF coil for tecknetics T2 (14kHz). I searched the web connectivity but I have not found. I made measurements on the connector but we must know whether he did it not integrated component in the coil .. (or other capacity). if anyone has any info on the connections of the coils could be used as ca.

On my diagram is not very complicated, all components are in the exact recommended value on the schematic of FOMA. and my PCBs from the site of REDRAM

The only difference is the value of capabilities that are tailored to my coils.

To answer your question, following the patterns of FOMA
(TX = 65 rounds of 0.28mm 1.33mH and RX 170 rounds of 0.22mm = 10.97 mH)

I measured 2.6 mH TX / RX 11ohms and 28.2 mH / 50 ohms.

I'll post the diagram connector coils and T2 readings tonight.

Maybe she could be compatible with the lobo. Legaucho said it worked okay, but he did not pursue testing ground ...

thank you for your help

[porkluvr]

Zoomix,
Here's something that might help us help you.

Start with a good coil - obtaining a factory coil is probably expensive, so otherwise use the data listed here. Coil probably needs to be properly nulled and I have NO idea how to help you with that; maybe somebody?

Now, draw or copy and edit a partial schematic showing the tx tank circuit, tx section and the component values you have installed. Show the RX coil value, coupling components, and rx block component values you have used. It would also be helpful if you were to show values of discriminate and GEB components and related components.

Post the partial schematic here in this thread. Don't send it to photo bucket or whatever, post it here.

Don't tell us what you didn't do, show us what you did do.

Maybe there's hope. Try it.

edit:
I apologize that my posts proably suggest that I have not read your problem from the start, and I have not. Reading about problems like yours just about makes me want to cry and I want to get IN and get OUT.

[porkluvr]

Zoomix can you clarify these two apparently inconsistent statements?

1) Following the advice of prédica2, I start to have a coil of 1.3mH and the 10.9mH...

2) After assembling the LOBO with the first coil (TX and RX 28mH 2.6 mH)...

What is what??

And where did you ever get the values of 28mH and 2.6mH? There has been a lot of confusion (which obviously still exists) ever since the Lobo schematic(s) became available, but what planet did you get these numbers from?

1.3mH +~11r (tx) and 10.9mH + ~51r (rx) (approximate values, this matches the data for the 5x10 coil) is almost certainly your best choice for working in the 19.5~20kHz region unless you know what you are doing and deliberately choose to deviate.

************************************************** *******

But this is all pretty much inconsequential, anyway. Let me explain.

You have made an extreme decision to attempt constructing a Lobo clone without a dual trace oscilloscope. There are so many variables that you have a very difficult task.

For instance, the adjustments on the transmitter are interactive. Both trim pots need to be tweaked in alternation until the final "best" tx setting is obtained. And then... there is the problem of aligning the rx phase to your phase detectors. Rx phase starts with the rx coil (!). But, then you have a dual preamp block with each and every component affecting rx phase. That is not an exaggeration.

Maybe somebody else will have a magic bullet and/or lots of time for you, but realistically, imho your chances are almost nil unless you can use a dual scope.