newcomer in need of help

[sähku]

Hi, fellow radio maniacs.

I'm from Estonia, and new to this forum. I'dont speak nor understand finnish, which is a shame - living in a neighbouring country and all...I hope I'm able to overcome this language barrier step by step. Maybe in the future even have some DX communications with you guys in your mother-tongue...wouldn't that be something

Ok, now to the problem: I got my hands on a Mocoma 59 CB transceiver, but the 40-channel modding tutorial is unfortunately only available in finnish:

http://www.radiohullut.net/mocoma59_1.php <-- this one

So...I has hoping that some english-speaking member of this forum would be so kind as to roughly translate the tutorial to me (or to us, from foorum.cbradio.ee). I tried to use google translate...but..yeah...I bet I understood more from the original finnish tutorial.

I'd be more than thankful, if someone would find the time and willingness to do this translation.

thank you, and see you on the air,
sähku aka raido

[oh2jin]

Tere Sähku

Welcome to the Finnish forum, probably we have already met in the Estonian one. Here we go with part one:

1. Irroita pikkuprintin ruuvit - remove screws of the small PCB
2. Irroita liittimet 4P ja 2P - remove connectors 4p and 2p
3. Vedä kytkinpaketti ulos - pull out the switch assembly
4. Käännä paketti ylösalaisin - turn the assembly upside down
5. Katkaise 3 foliota (kuva) - cut three connections on the PCB


DX jää päälle ja lisätään kanavia:

Ruuvattuasi kytkinpaketin irti koneestasi olet huomannut, että printistä lähtee kaksi johtonippua. Toisessa on kaksi ja toisessa on neljä johtoa (kuva). Nämä kaksi johtoa jotka menevät koneen keskiosassa olevaan liittimeen (P2) ovat DX/LOC:in johdot.


DX is always on and additional channels are modified

After the switch ass'y is removed locate two cable harnesses running from the PCB. In the first cable harness there are two wires and in the second one four wires, see the attached picture. These two wires which run to the conector p2 on the main PCB are DX/LOC wires.


Irroita ne johdot kytkinlevystä sekä juota johtojen päät toisiinsa. Ota kytkin printiltä irroittamasi vastus R401 (47-52K). Etsi pääpiirilevyltä jostain kohtaa DX/LOC johtojen liitimen läheltä maa (GND) ja juota vastuksen R401 toinen pää siihen ja toiseen päähän samaista vastusta ne äsken yhteenjuottamasi johdot. Näin tehtyäsi kytkeytyy DX/LOC niinsanotusti "herkimpään" tilaan pysyvästi. HUOM! ..kun etsit maapistettä johdoille on syytä muistaa, ettei LA-koneen metallirunko ole galvaanisessa yhteydessä maahan.

Remove those two wires from the switch ass'y PCB and solder them together. Remove R401 from the switch ass'y PCB. Locate the GND potential from the main PCB. Solder the other end of the resistor R401 to the GND potential. To the other end of the resistor those two wires should be soldered. Now DX/LOC is in its most sensitive position. Remember that the steel frame of the transceiver is not at the DC ground potential.

More to come, standby...

[oh2jin]

I translated the rest of the text and pressed the "send" softbutton. And this forum threw me and my text out and asked me to log on.

Anyway the original text is rather difficult for me despite I am a native Finnish speaker.

[oh2jin]

Not gonna risk missing any text this time

Irroita DX/LOC kytkimen nastat (6kpl) esim. tinaimusukkaa käyttäen. Kokonaan kytkintä ei kannata irroittaa riittää kun nastat on tinasta vapaat. Katkaise kytkimen puoliskoja yhdistävät foliot esimerkiksi mattopuukolla (kuva). Lopuksi varmista yleismittarilla, että katkaisu onnistui. Toisella kytkimen puoliskolla oikosuljetaan PPL-piirin nasta: 7 halutessa maahan.
Juota irroittamasi vastuksen R401 paikalle "hyppylanka" ja aiemmin irroitamasi vastuksen R402 etulevyn puoleiseen jalan reikään johdon pätkä joka pituudeltaan riittää pääpiirilevyn juotospuolelle PLL-piirin nastaan: 7.
Viimeiseksi juota kytkimen puolelta tuleva ko. puoliskon nastoista keskimmäinen ja eulevyn puoleinen yhteen.

Desolder the pins of the dx/loc switch. Do not remove the switch. Cut the copper films connecting the switch halves together. Remove R401 and R402. Replace R401 with a jumper wire. Connect a wire at (empty place of) the R402 fronte PCB end. Connect the other end to the PLL IC pin 7. Connect the center and the front PCB side pins of the switch together.

[oh2jin]

AM-moden esto yläkanavilla ja lisäkanavat näyttöön:

Näyttöön on myös syytä saada lisäkanavat näkyviin. Tarkastele seuraavaksi kytkinlevyn alapuolella olevia kanavanäytön vastuksia R120 - R133. Kyseiset vastukset ovat vieretysten pääpiirilevyllä.

AM inhibit and enabling channel display on upper channels

There are resistors R120-R133 side by side on the main PCB

TARVITSET SEURAAVAT KOMPONENTIT: (required components)
-diodi . . . . . . . . .1N4148 3kpl (tai vast. signaali diodi)
-transistori . . . . . BC535 2kpl (To-92 - jalkajärjestys B. C. E.)
-vastus . . . . . . . .39KOhm
-vastus . . . . . . . .10KOhm


Katsele seuraavaksi koneen pääpiirilevyä juotospuolelta. Juota vastusten R129, R130 ja R131 laitteen sisäpuolelle osoittaviin liitosnastoihin (ei siis etulevyn puoleiseen) 3 diodia siten, että kaikissa on yksi. Anodipää diodeista vastuksiin päin. Tilaa siinä ei paljo ole, mutta tarpeeksi pienellä kolvilla / kolvinkärjellä homma kylläkin onnistuu . . . etenkin niin ettei oikosulkuja synny juotosten välille.

Connect a diode to each of the resistors R129, R130 and R131. The anode is connected to the resistor terminal farthest from the front PCB.


Juota PLL-piirin nastaan: 7 NPN-transistorin kollektori. Juota kytkimeltä tuleva johto transistorin emitteri jalkaan sekä lopuksi kantaan 10KOhm vastus. Vastuksen toiseen jalkaan johto joka ylettää AM/FM kytkimelle koneen pikkuprintille juotosnastaan: 7 (valkoinen johto tulee samaan nastaan) Seuraavaksi juotellaan 6-7cm pitkä johto PLL-piirin nastaan: 7, johdon toinen pää juotetaan diodeihin 129 ja 130.


Connect the collector of the NPN transistor to the PLL IC pin 7. Connect the wire from the switch to the emitter. Connect a 10k resistor to the base. Connect the other end of the resistor to the AM/FM switch pin 7. There is already a white wire on that very same pin. Connect a wire to the PLL IC pin 7 and the other end of the wire to the diodes D129 and D130.

Samaan nippuun juotetaan toisen NPN-transistorin emitteri ja saman transistorin kollektori juotetaan vielä vapaana oleva diodi joka olikin jo aiemmin tinattu vastukseen 131.
Transistorissa on yksi jalka vielä vapaana siihen juota 39K vastus ja vastus juotetaan vastuksen 132 koneen puoleiseen päähän (samaan riviin kuin aiemmin diodit).
Nyt kun nämä työvaiheet olet onnistuneesti suorittanut Mocoma 59s on muuttunut kuin taikaiskusta Mocoma 59ss malliseksi ja se toimii Ch: 1-22 AM/FM ja Ch: 23-39 FM taajuuksilla. AM-mode estyy automaattisesti kun kanavan valitsimesta käännetään yli Ch: 22 :sen jolloin kone siirtyy FM-modelle.

The emitter of the second NPN transistor is connected to the same point as PLL IC pin 7. The collector is connected to the only free diode which is already connected to R131. The base is connected to a 39k resistor. The other end of the resistor is connected to the inner side of the R132. This is the same and where the diodes are connected on the other resistors.


===

As I said very difficult text indeed, even for native Finnish speakers. But the picture and the PCB hopefully explain the correct procedures. I have done this but with a different method. My advice is that the circuit diagram should be dealt with before making any of these changes. Somehow I feel little uncomfortable with this text...

[sähku]

hello, grindstone

Thank you for taking the time to do this, really.

Ouch, that must have hurt...forums sometimes do that...I've experienced my share of these "pleasent surprises".

Yeah, I know...this is a difficult text...hope you didn't go through too much hassle because of my request.

Hmm...okay...I'll try to be observant while performing these changes. Maybe get some background info first...we'll see. I'll post the results here, anyway

PS: laughing...this just happened to me too...I'm writing this the second time


sähku

[meikäläinen]

Good luck with your modifications
Thanks to Slipsten too!

[oh2jin]

There are the PLL IC pins required for this mod

http://tiiliskivi.com/hoto/modif.html#mocoma59

RX/TX-laajennus
-PLL-piirin LC7132 jalan 7 maadoitus
--> 1=21, 2=22, ..., 19=39
-PLL-piirin LC7132 jalan 8 maadoitus
--> 10=40

RX/TX channel expansion

In the original 59 unit the most elementary level of modification is as follows.

PLL IC LC7132 pin 7 connected to DC ground. Then you'll get channel 21 while your display shows 1. Respectively channel 2 on display means working channel 22 and so on. Wen you select channel 19 your working channel is 39. Connecting the pin 8 to DC ground provides you working channel 40 when your channel display shows 10.

Now we know the logic for manipulating this PLL IC LC7132 in order to select all the 40 working channels. Unfortunately this chip does not allow to expand the channels more due to the factory pre-set PROM settings. However, in case someone considers feasible the mixer loop can be modified.

Regarding Your project the challenge from now on is to design and implement the necessary logic controlling both the PLL IC pins 7 and 8 as well as the channel display in "extended channel mode".

[oh2jin]

Sähku and co can find there Sanyo LC 7132 PLL IC data sheet

http://www.datasheetcatalog.org/datashe ... LC7132.pdf

Take a good look at the manufacturer's recommended typical application on page 4 and cearefully read the theory of operation before that.

[sähku]

Yep, I'll do that...at the moment I'm trying to put my mind around the LED display, and trying to find the best way to manipulate it. It seems to be a common anode (I might be wrong) display...the channel selector switches earth where and when needed. Turning a required segment on and off myself without interfereing with the 1-22CH range is quite a challenge to me First I have to understand, how this is accomplished in the tutorial...will it actually work...and if/how can I add the 40-th channel.

EDIT: hmm...when looking at the typical application schematic...it seems that the display segments can be directly connected to the PLL programmable inputs. This isn't the case with Mocoma...because when I ground the PLL pin 7, no segments light up. The channel selector probably has two separate "tracks". Maybe I could wire it differently, similar to the typical application schematic...have to give it a thought.

sähku

[oh2jin]

According to the schematic diagram the display unit is common anode type indeed. Unfortunately I do not have any 59 units in my fleet any more, only the diagram. I sold my last working 59 unit in early 2009 and two severely damaged units in late 2009. But I remember the channel selector has separate contacts, or sets of bits, for controlling the display and the PLL bits. I didn't care the display when I modified some of my units.

Probably You must figure out two truth tables, one for PLL control bits and the other for display control bits. I assume that there must have been similar channel selector units of 40 slots instead of 23 for markets where 40 channels were allowed those days.

Also, please be aware that the modification procedure descibed in the document hosted on this site disables the AM mode on the upper channel bank.

[sähku]

Well, hi again. I finally got around to performing the mod. I followed the tutorial, except for the AM disable part. I really can't figure out why AM is turned off in extended channel range I left this part out and everything seems to be working OK.

40-th channel...yeah...no good news there. Staring at the PLL thruth table and wiring schematic haven't proved useful so far. I need a second switch, and a bunch of transistor logic to get the 40th channel to display correctly.

I'll try to figure something out when I "run into" some spare time

73!
sähku

[oh2jin]

When the upper channel bank was allowed here in Finland the AM mode was prohibited there. Only FM was allowed on channels 23-40. Also the old AM capable units, or their licenses more likey, were due to expire in 2004. However the new regulations introduced meanwhile allowed SSB and AM on all 40 channels as well as FM. Also, one can argue that his or her rig can have whatever modes and maximum power levels and it is still rather difficult to figure out it is illegal on the basis of emitted signals. Provided the regulations and restrictions are srtictly followed thus questioning the sensibility of the AM disable circuit at once.

Channel 40 is enabled on the PLL IC by grounding pin 8. This is, according to my best understanding based on the schematic and the application note discussed above, the only event where this bit is needed. One rather theoretical workaround is trigger, or address more likely, by this bit a byte from auxiliary ROM or diode logic.

Perhaps some of us who has access to 59 unit can help You. As I said, I have sold all of my 59 units as I considered them obsolete.

[sähku]

Oh, please, no help needed Besides, You have already done more than enough. I have to figure this one out myself...how else will I learn