uniden washington MB8719 Ch mod

[KD2GOE]

I am looking to add the upper Ch uniden Washington but it is telling me to Locate and unsolder the 11.1125 crystal and replace with a new 11.3258 crystal why is this? why cant I just add the switches to the PLL?

and it the instructions it tells you do align "if needed" would it be way off adding the new crystal?

 

[loosecannon]

leaving the 11.1125 crystal in there will give you 26.175-27.455 i believe.

the 11.3258 crystal would give 26.815 to 28.045.

just so you are aware, your radio will need an alignment afterwards no matter what.

the VCO will most likely need a slight adjustment.

you cant do freq mods without a real frequency counter.

sure, you may get lucky and only be off by a marginal amount, but you wont know whether it worked or not without the counter.

also, the radio needs to be realigned after the freq mod or you wont have good sensitivity on your new channels.

if you are determined to try this, here is a link to a mod that uses the 11.1125 crystal and claims to get the high range also.

BE WARNED!!!!!

i have not tested this mod, and it came from Secret CB which is well known for its many mistakes and typos.
http://www.cbtricks.com/pub/secret_cb/index.htm

my opinion is that you should NOT try it, but i always post the info anyway.

LC

 

[sonoma]

Loosecannon is right, you can do it with out the crystal change and either way you go you will need a freq counter to verify what freq is on each channel so you will know where you are at and the radio will need to be aligned to get it on freq after the channel mod is done to it.
tools needed.
freq counter
volt meter
scope.
this is the bare minimum needed to do it right.

 

[hotrod]

i have a washington done up with lower/higher channels on the push buttons
but it skips 27.415- .4550 .why is this?????

 

[sonoma]

here is a chart to mod the PLL's on most radios.just for everyone that does not have it.more than likely the mod for those freq was not done if it is a 858PLL. look at the chart I just posted.

PLL Frequency Mod Diagrams

 

[loosecannon]

great link sonoma!

good to have all that info in one place.
LC

 

[hotrod]

here is a chart to mod the PLL's on most radios.just for everyone that does not have it.more than likely the mod for those freq was not done if it is a 858PLL. look at the chart I just posted.

PLL Frequency Mod Diagrams

mines not the 858 mines mb8719..i think thats right? mine seemed to be right only on here
it shows a 6 position knob, wheres mines on 2 pushbottons on lower right corner to keep
the stock look.thanks for posting that

 

[hotrod]

mines not the 858 mines mb8719..i think thats right? mine seemed to be right only on here
it shows a 6 position knob, wheres mines on 2 pushbottons on lower right corner to keep
the stock look.thanks for posting that

actually i looked that over again and just seen theres 2 versions for the mb8719
the first one seems right on with mine. but the second has has more freq. slightly
above 40.

 

[sonoma]

I have used this info for channels for years and it has worked good for me. it has about all the PLL mods you need. it is very self explainatory also. very easy to follow. the drawings are from the botom of the board as you would look at it doing the soldering.

 

[melaza]

Hi,
the one in secret cb is fine, just change the fixed resistor for a 10k variable resistor. Some components need to be changed and cut one resistor.

Greetings from Desecheo Island op:

 

[KD2GOE]

ok I have a 8 digit frequency counter and alignment is not an issue.




after doing more reading I think I may just fined an HF radio and mod that. I am well capable of doing the mod I just don't want to hack my radio..

 

[sonoma]

Hi,
the one in secret cb is fine, just change the fixed resistor for a 10k variable resistor. Some components need to be changed and cut one resistor.

Greetings from Desecheo Island op:

not sure what mod you are talkiing about here. we were talking about doing a channel mod to get more channels. are you talking about unlocking the clarifier. not sure what you are saying here

 

[melaza]

Secret CB Vol. 14 page 11 (channel mod).

 

[sonoma]

Secret CB Vol. 14 page 11 (channel mod).

OK thanks, I have never done this one due to getting all the channels to lock in and so many switches. I normally just due the mod that starts at 26.815 or about there. I normally just put a rotary switch in the head phone jack hole and use a 3 position switch to get all the channels I ever use on the radio.
thanks for posting this one. this way we know what one you are listing.