TRB-1 installation questions

[loosecannon]

hi all,

ive never owned one of these boards before and im going to put one in my uniden PC78XL (same as 29LTD) tomorrow.

my main question is about the negative power lead.

in the instructions, it states to solder this lead to the ground pin of the mic connector.

is there a reason they want this lead soldered to the mic connector instead of to the nearest tuning can?

also, what is your normal procedure for adjusting VR1 and VR2?

i am going for that touch of echo in your audio type of sound. i could care less about endless echo and such.

VR1 is the output gain, as this board incorporates a mic amp circuit into its design.
how do you folks run them?
all the way up, down, or what?

just looking for opinions from those who have played with these boards.

any other insider tips on installing and adjusting these boards is appreciated.

thanks,
LC

 

[Robb]

http://www.cbtricks.com/miscellaneo...oys/magnum/trb_1/graphics/trb_1_inst_2006.pdf

I dunno if that link helps.
I read it thru and it does tell how to set it up for 'optimal performance'. Some reviews have said that it will be a bit touchy to get it right. I've never put one of these in, as all of the radios that I use already have them in it. The Magnum radio I have has a really clean echo; and I expect that your TRB-1 will be of the same quality as well.

Keep us posted with your work!

 

[fnkycoldmedina]

lc

when i install a echo(and ive installed dozens apon dozen over the years)i always solder the power ground to a tuning can.this is the norm.
now as for the audio ground leads they both get soldered to the ground pin at the mic connector.

are you sure you arent confusing the 2?the instructions should clearly say to solder the audio lead grounds to the mic pin.not the power ground.

anyway...i always crank the onboard amp all the way up .now thats just me but i crank them all up.you do want blazing modulation right?

if its too loud with a power mic afterwards just run a skythumper or rk56 or something .

i turn em all the way up,i do work for guys at a trucking outfit and they usually run a rk56 or 636 so they need that boost.i run all my personal boards wide open too and i still run a power mic .
i just barely need to crack open the mic on the first setting but i can always run one .

you will get good blazing modulation with it all the way up .i have never had a complaint from anyone doing this .more like flowers all the time .

good luck.

 

[loosecannon]

rob, thanks for the link.

i will be doing this either today or tomorrow, depending on how long it takes me to do the other upgrades im going to do. (channel guard, receive kit, LED meter lights, and im sure a couple of others)

fnky,

thanks for the advice.

nope, im not confusing the two; thats why i asked, it seemed strange to me to put power ground on the mic pin. the audio shielding i understand, but the power ground thing threw me.

here is what the TRB instructions say:

"solder the negative TRB-1 power lead (wire 2 from J4) to ground pin on the microphone jack."

i think the reason they said to do it this way, is that they have to take into account the lowest common denominator of installation knowledge.
like, any other way they explained where to put the ground, 1% of people would misunderstand it and think that their TRB didnt work right.
who knows. LOL

thanks for the confirmation on the tuning can, thats what seemed logical to me.

also thanks on the tuning advice. i will be running an astatic 636, so im going to turn mine all the way up and see how it sounds.

i will post back when i get it installed.
LC

 

[loosecannon]

ok, all installed and working!

i put in a channel guard, the 2999 receive mod, a swing mod, talkback, the TRB-1, and dual LED meter lights.


all seems to be well, and the radio keys at 2 watts and swings to about 20 or so.

good enough for me!

i could not turn the TRB all the way up like was suggested though.

seemed to squeal as i approached 3/4 of the way up.
that was with the AMC pot turned all the way up and the mic gain on the radio all the way up.

i decided to run it with the TRB most of the way up and adjust the mic gain down just a bit.

seems to be running well, just need to get used to it.
later, and thanks for the help,
LC

 

[Switch Kit]

squeal huh ? I still say the TRB-1 is the best board I've ever used over the years (in any radio) Your radio should not squeal period at any volume unless you have a talk back resistor that is to low in resistance ? (or a bad ground)

I have always put "all grounds" to the mic pin grounds as suggested with the TRB-1. It doesn't mean a can or chassis ground wouldn't work , the directions call for (mic pin ground.)

Stray RF from these boards can cause squeal as well , I always cover the board in a big hung of heat shrink tubing or cover nicely in electrical tape completely. (weather mounted inside , or nicely shoved under the front end wires and secured)

Even for just a touch of echo/reverb , I still find the TRB-1s to be the best. They can be slightly touchy , but still the best. Good luck to you LC.

 

[fnkycoldmedina]

if it in fact says all grounds to mic pin then thats to avoid ground loops.
if you do go to the can and have problems with the board then do add that ground to mic pin then .

 

[loosecannon]

ok, i will give it a shot.

i do know that co-locating all your grounds is a good idea to avoid ground loops so why not!

i mounted it on the right side of the radio towards the front (radio upside down).

this way, it was close to the mic connector, and seemed to be a good location.

i now see that the speaker is very close to the connectors on the TRB board.

where do other people mount them in the 29LTD/ PC78XL chassis?

thanks for the input guys,
LC

 

[Switch Kit]

squeal huh ? I still say the TRB-1 is the best board I've ever used over the years (in any radio) Your radio should not squeal period at any volume unless you have a talk back resistor that is to low in resistance ? (or a bad ground)

I have always put "all grounds" to the mic pin grounds as suggested with the TRB-1. It doesn't mean a can or chassis ground wouldn't work , the directions call for (mic pin ground.)

Stray RF from these boards can cause squeal as well , I always cover the board in a big hunk of heat shrink tubing or cover nicely in electrical tape completely. (weather mounted inside , or nicely shoved under the front end wires and secured)

Even for just a touch of echo/reverb , I still find the TRB-1s to be the best. They can be slightly touchy , but still the best. Good luck to you LC.

as I said before.......... you may be best to not mount the unit LC in that radio. Insulate the board as mentioned , and put under wires on the front end of the radio in a secure manner. This would be the side away from the PLL. (weather it matters or not)

 

[fnkycoldmedina]

on a cobra 29 chassis i mount mine just behind the channel selector on that side and i drill the holes and using the mounting screws .
you have to measure first and put a mounting knob in the radio for reference.this is most important .if you mount the board first and not check the clearance for the mounting bracket knob ...could be disastrous later .
that said i check the mounting location carefully and mount the board component side up ..facing me..
if your precise with your mounting you can leave the speaker in the radio.
i add electrical tape to one half the inside of the speaker to be safe .
you can close the radio up and look down the crack in the chassis /radio case with a good powered lite and see if anything is touching .

i use the tape and ive done enough to know the "sweet spot"but taping that side of the speaker sure dont hurt .

you could probably get away without doing that part if you mounted the board solder side up inside the radio .but the you must set the board befor you screw it in .

good luck.