MC145151 PLL

[zodiac]

Has anyone ever used or fitted a MC145151 PLL to a CB radio.
My intention is to fit one in a 3900 to give it the facility to switch down to the zero's.
The MC145106 runs out of binary when pin 6 is switched on even with a crystal change for one that's higher than the original.
The MC145151 has a hell of a lot more binary pins of which I only need one more and using an Eprom would make it possible to keep 6 bands starting at 26.065 up to 28.305 with the UK band. All the FCC bands would switch down to zero with a flick of a switch, instead of waiting for them to speak before you can tune them in.
I've done it before using the MC145106 on FR 360's an Adams and WKS 1001's but they only had 4 bands and required the crystal's changing to 11.059, well I had a load of them for free.
I would like to remove the MC145106 completely and just use the MC145151 but if I have to use both them I will.
At present it's just a project that's been running through my mind for years but I only just found the PLL's I new I had somewhere.
The reason I'm using an Eprom is because I have plenty of them at present and it's makes it easy with just one IC required and no diodes or binary adders to go faulty.
Any information would be gratefully appreciated.

Dave.

[The Defpom]

Hi Dave,
I have used that PLL with an EPROM, only I moved all the inputs over by 1 bit, and set it for 5KHz steps, then the lowest bit can be manually switched to give a 5KHz shift.

It is a very versatile PLL, and is able to be configured for many different situations, negative and positive going PD etc.

If all you are wanting to achieve is the 5KHz shift function, then you could just replace the existing PLL with the 151 and do like I just mentioned about moving the inputs over by 1 bit and setting it to 5KHz steps, that will give you what you need, no EPROM or extra programming needed.

[zodiac]

Thanks for the encouraging reply Scott, that's just what I needed to know, that it will work.
I've asked the same question on other forums and so far only had one sensible rely and yours of course.
Now I need to work out the pin connections and I must add they do confuse me as to which to use and which not to use.
I have wired it as per the diagram but I only get 24.5?? no matter how I set the binary input switches.
So far nothings getting hot and I've not blown the PLL yet.
If you can remember how you wired it maybe you can tell me what I've done wrong.
Dave.

145151.png (10.32 KiB) Viewed 28021 times

[The Defpom]

Hi Dave,
Hopefully we can get to the bottom of it.

Pin 28 should be connected to 0V through a 220pF ceramic cap to help load down the LD output (minor detail)

You have the 8V and 0V markings back to front on pins 2 and 3, pin 2 is 0V, pin 3 is 8V.

For 10KHz spacing you want RA0 and RA1 to be low, and RA2 to be high (left disconnected), so pins 5 and 6 should be low, and pin 7 disconnected. to give a divide by 1024, which is required for 10.240MHz xtal to give 10KHz.

I remember you wanted 5KHz steps (with the bits shifted over by one to return to 10KHz steps, with a 5KHz switched offset instead using the lowest bit), so you need to divide by 2048 instead, which means that you need RA1 low, RA0 and RA2 should be high, (so pin 5 and 7 should be disconnected, and pin 6 should be pulled low).

Leave pins 8,9,10,21,26 disconnected, you can ignore those, if you are not going to be using the LD output (pin 28) you can leave that disconnected too.

Let me know how you go.

[zodiac]

Thanks Scott,
Good job I didn't wire them the wrong way round, that's through rushing, so I've corrected it to how it's wired.
I've wired it as you said Scott and it's no different also the KC shift doesn't work, again and again
Dave

[zodiac]

Thanks Scott,
It's working now Iv'e cut all the wires shorter and found a wire in the wrong position on the main board.
Thanks again Scott, all I needed was a bit of encouragement.
Now for some fun.

Dave.

[rf-doc]

Hi,
really nicely this old 145151.

Where can I buy this obsolete 145151?

For different mod's (my old Stag 357, Universe+Palomars with the "stupid" LC 7130 Rom-fixed PLL) I take "Gerhard-made" smd-modules. However, they work with the serial MC 145158 and are steered with µController

Klaus

http://www.hf-doktor.de.pn/

[zodiac]

Hi Klaus,
How many MC145151 PLL's do you want ?, I do have some but not too many.
I converted about 6 Stag 357's with the MC 145106 PLL to 4 bands ( 26.065 to 27.855 ) with zero switching using pin 6 of the PLL with an EPROM, good old radios the Stag.
Dave.

[zodiac]

Klaus,
You can still buy the MC145151, google MC145151 PLL, below is just one add for them.

Integrated Circuit
Stock and Pricing Details
Stock Status: Available in Stock - Shipped in 5 Days
Price: £14.25
Excluding VAT for UK & EU deliveries
Quantity: Add to cart


Wholesale Prices
Quantity: 1-9 Pieces 10-19 Pieces 20-49 Pieces 50-99 Pieces 100+ Pieces
* Price: £14.25 £13.89 £13.54 £13.18 £12.83

* Note: Excluding VAT for UK & EU deliveries 5 days

[Animal]

Dave

I wouldn't mind this mod doing to a President Grant (PC-999AE)

Will it still need a +10kHz shift adding (it's standard at the moment) or does it step 5kHz continuously after the mod?

Cheers

Steve

[rf-doc]

Dave

many thanks for your answer and tips.

I look for inexpensive alternatives to e.g. LC7130 and/or PLL smd modules
to experiment and of course curiosity

I love the old radios like Stag, WKS, Universe and Palomar

Have some, unfortunately, most with the LC7130 board

I also have mod some, e.g., with switchable mode for channel (1-80 german ch., 1-40 CEPT/FCC and 41-80=26.565-26,955 below without hops) or simple frequency display with 10 KHz steps, continuously without band-sw, 5 / 0 KHz shift, FM board, scanner, up/down via mic...

thanks and sorry for my poor bad english

Klaus

[zodiac]

What MOD Steve ?.

[Animal]

What MOD Steve ?.

Dave - It's a great idea using the MC145151 to get 5kc steps rather than waiting for someone to call on the zero's then calling them back!

Would it tune continuously or would it still need a 10kc shift added to get the alpha's?

Steve

[zodiac]

Steve,
I am working on an Eprom to use with the original MC145106 PLL that's fitted to the radio, that will give the zero switching, the only thing is it may need the crystal change. Then you'll need a 4 pole 5 position rotary switch, as fitted in the Cybernet SSB radios like the Tristar 777, Nato 2000, Superstar 200, and others but I can't remember then all, it's been a long time I last did one.
The amount of shift will not change, that stays as it is and the Alphas are programmed into the Eprom so that if your not on the Alpha channel you don't go up a channel, that's why it needs the 4 pole switch to switch 4 things at once.
The reason for using the MC145151 is, that it has a lot more binary pins than the 145106 and you only need one extra binary pin.
When you switch to the zero using pin 6 of the 145106 PLL you have to double the binary number to be on the same channel, by using one number less than the double number you go down one channel to the zero as your counting in 5kc's per channel instead of 10kc's.
You can stop scratching your head now and start saving your money for when I've done it, if I get the chance.
I've got a customer in Scotland screaming for the conversion to two Cobras he has but I've been so busy with my fag money on other radio.

Dave.

[zodiac]

Klaus,
Spectrum Communications in the UK have the MC145151P at £6 plus post.
Dave.

[zodiac]

Steve,
I forgot to mention that I did about 6 or 7 Grants many years ago with zero switching from super low to the UK 1 to 40, with Alphas and without unlocking the clarifier. I used one crystal for the 4 FCC bands and one just for the UK band so it could be tuned for the UK offset of 1,25kc's on FM.
Still got the Eprom program and the band switch drawing for it.
Dave.