mosfets

[ken white]

When looking at the front, the three legs of the ERF 2030 are, from left to right; gate, drain and source. I don't know what the CB repair guy meant by "the base leg" please help me out on this. which leg would I jump to the positive of the EN 1230?

With the thing facing you, the left leg should be the base.
That is what it looks like on the spec sheet for a 1969 final.

pin 1 - base
pin 2 - collector
pin 3 - emitter

From left to right.

After I posted, I found a spec sheet of sorts for the ERF 2030 and the legs are definitely gate drain and source. Is base another name for the gate leg? Until I get confirmation on the jumper from the 1230 to the 2030 I am going to leave that out.

base is analogous to gate
collector is analogous to drain
emitter is analogous to source

 

[Xy3lon4]

When looking at the front, the three legs of the ERF 2030 are, from left to right; gate, drain and source. I don't know what the CB repair guy meant by "the base leg" please help me out on this. which leg would I jump to the positive of the EN 1230?

With the thing facing you, the left leg should be the base.
That is what it looks like on the spec sheet for a 1969 final.

pin 1 - base
pin 2 - collector
pin 3 - emitter

From left to right.

After I posted, I found a spec sheet of sorts for the ERF 2030 and the legs are definitely gate drain and source. Is base another name for the gate leg? Until I get confirmation on the jumper from the 1230 to the 2030 I am going to leave that out.

base is analogous to gate
collector is analogous to drain
emitter is analogous to source

So am I going to be cool jumping the positive leg of the EN1230 to the Base of the ERF 2030?

 

[ken white]

...So am I going to be cool jumping the positive leg of the EN1230 to the Base of the ERF 2030?

I have no idea... Sorry

 

[funbiz99]

Xy3lon4
when u r done post pics & before & after results

 

[bushwacker]

When looking at the front, the three legs of the ERF 2030 are, from left to right; gate, drain and source. I don't know what the CB repair guy meant by "the base leg" please help me out on this. which leg would I jump to the positive of the EN 1230?

With the thing facing you, the left leg should be the base.
That is what it looks like on the spec sheet for a 1969 final.

pin 1 - base
pin 2 - collector
pin 3 - emitter

From left to right.

After I posted, I found a spec sheet of sorts for the ERF 2030 and the legs are definitely gate drain and source. Is base another name for the gate leg? Until I get confirmation on the jumper from the 1230 to the 2030 I am going to leave that out.

base is analogous to gate
collector is analogous to drain
emitter is analogous to source

So am I going to be cool jumping the positive leg of the EN1230 to the Base of the ERF 2030?

Its not going to short out or anything..... the base is the input or when talking about mosfets it would be the gate. Its called a base with bipolar transistor and a gate with mosfets.
Either way its your input.... there is normally supposed to be a resistor between the gate (or base if you want to call it that) and the en1230.... its resistor R123. That resistor is for drive input... in alot of cases it will also affect the gain of a transistor. Usually its normal to change the value of this resistor to one of a lower value.... what your doing in your mod is taking it out completely. So basically you will have no resistance at the input (base or gate) of the transistor. This may be ok for a FET... but with some transistors a bit of input resistance usually helps... I've found with 1969's its best to just change the resistor with one of a lower value or just leave it be. 1969's need some input resistaance... at least they do when I mod a radio. Its very common to change the resistor for the driver transistor... prety much every cobra 29 mod on the nets involves changing this.

So.... your ok to try this out... basically your just jumping this resistor out... it might help matching the impediance to the fet. It could also add more drive to the Fet.
This is just speculation. But its ok to try it... weather you get more out of the fet by just lowering the resistor value or by jumping it out I can't say. Its worth a shot.

No harm in trying it... your good to go. Its definatly possible you could get more power out of the fet either by better impediance match or more drive.
If you don't get a big increase in power........ take the jumper out and try it with the resistor in.
Give it a shot, its worth checking out

Take care

 

[lords]

what radio are you moding?????

 

[Xy3lon4]

Xy3lon4
when u r done post pics & before & after results

I already did the CB tricks mod. I am waiting on parts to complete the mod. I would like to know how to do a down and dirty peak and tune so that I don't have to take it to a CB shop.
The next radio I do it on, I will take photos.

 

[Xy3lon4]

what radio are you moding?????

Cobra 29 LTD

 

[lords]

ok so whats the problem with the standard mod
for it?

 

[Xy3lon4]

ok so whats the problem with the standard mod
for it?

If you are talking about the standard CB Tricks mod, it will only give you between 15 and 25 watts without the limiter clipped. According to the tech that I got this mod from it will increase the power to around 50 watts maybe more with the 4.7K resistor added.

 

[funbiz99]

ok so whats the problem with the standard mod
for it?

i did the standard mod as was not impressed........when i jumped the diode and added the 4.7k resistor it was much better.....after i see the results here i am going to volt the pre driver.

 

[Xy3lon4]

ok so whats the problem with the standard mod
for it?

i did the standard mod as was not impressed........when i jumped the diode and added the 4.7k resistor it was much better.....after i see the results here i am going to volt the pre driver.

Either I did something wrong or the instructions I was given were bogus. Didn't smoke it though. I am going to take it to a cb shop and see if they know what I did and can either do the mod right or put it back the way it was.

 

[lords]

well nice try anyway

 

[bushwacker]

Your doing alot of excess jumpers for very little gain in power. Jumping 12 volt power into the buffer isn't the best for the radio.... and it doesn't net you alot. Usually when you jump over you also have the modulation going into the buffer... this will give more forward swing ( a bit anyways).
I don't recommend to anyone to jump power to the buffer but it can be done and I have done it myself. The radio is better off with switched power on the buffer with the origonal 8 volts.

Walk through the problem... do you have voltage going to all the transistors? Do you have any output power? If so how much? If you have no output power, hook up an amp meter inline with the power running into the radio (series with the positive wire) and check if you get a current increase when you key the mic. If you have a current increase but no output power... the rf is just not getting out. Which means there is an open connection somewhere.

If I remember this mod right.... you jumped from L15 to L17?
Wait let me check......

Ok thats what you did... What side of L15 did you jumper to? The side closest to the transistor? or the other side? If you jumped it closest to the transistor you did it wrong.At that point you have 12 volt power meeting the collector and rf power coming out. The reason that coil is there is so no rf power get out through the 12 volt input.... its an rf choke. On the oposet side of this choke (l15) you will have 12 volt power and modulation.... no rf.
So if you jumped the power from the wrong side of that rf choke L15, alot of the rf output from the final can be getting routed back into L17 insted out out.

Really it could be alot of things but you should be able to figure it out and get it back to normal.

Make sure you have voltage going to the final for a start... L15 is what brings the voltage to the final... without that hooked out there is nothing powering the mosfet.

Take care...

 

[Xy3lon4]

Nope, CB dude is going to figure it out.