Uniden 980 not transmitting

[SuperLid]

I hope you have enough spare drivers and finals to get the job done ...

I was thinking the same thing. Total waste of good bipolars.

 

[vswr]

You do realize, that the Mitsu final is no longer used in the current production units?

Ive heard that. I dont have the second gen to compare it with. I know that they removed that little board in the back of it. Thats all I know about it. Without a schematic its been a real treat NOT finding my way through it. Lucky its the finals. Simple layout. Id hate to have to figure out the oscillator path for am and ssb on this. Tracing it all through to wherever the pll is located would be a nightmare. Have you heard of a drop in fix? Someone sent me the pres mckinley sm but its completely different from this one. Maybe the same as 2nd gen but again, I dont have one.

 

[vswr]

and i got 2 ,removed 1 from use. not sure if im fixing it or selling package deal. expensive junk

Seems so

 

[vswr]

I was thinking the same thing. Total waste of good bipolars.

Could be a waste but maybe all it needs is a 1306 and 1307 set from an old 23 ssb. Vcc is the same, ground is ground, a littlr biasing and a coupe of protection diodes across the finals just might work. I got spare parts and im retired so it'll be a winter project.

 

[vswr]

i got 2 of those cheepo radios
sadly if uniden woulda invested a itty bit more $$$ they could built a best radio.
i removed 1 from service in 1 of our big trucks that couldnt take it . not used much either. as soon as i finde right radio the other 1 is coming out of truck #2.
if somebody dearly loves these radios id gladly trade em off or sell em

So true. I find that there are a lot of really good features on it and the ears are remarkable. The pots are kind of fragile it seems. Only bitch really is the mits rd16hhf1 and thats because the mosfet has poor internal protection. Maybe the old diode trick between the drain and source in reversed hook up might save the chip from frying if it forward biases the diode but then the diode may short and let the smoke out of the mosfet anyway. I dunno. Im still thinking of ripping that crap out and slapping in old school bipolars.

 

[SuperLid]

Ive heard that. I dont have the second gen to compare it with. I know that they removed that little board in the back of it. Thats all I know about it. Without a schematic its been a real treat NOT finding my way through it. Lucky its the finals. Simple layout. Id hate to have to figure out the oscillator path for am and ssb on this. Tracing it all through to wherever the pll is located would be a nightmare. Have you heard of a drop in fix? Someone sent me the pres mckinley sm but its completely different from this one. Maybe the same as 2nd gen but again, I dont have one.

Perhaps you can find internal photos and compare them visually. The newer final is an equivalent of the IRFZ24, which seems to be robust and dirt cheap.

 

[SuperLid]

Could be a waste but maybe all it needs is a 1306 and 1307 set from an old 23 ssb. Vcc is the same, ground is ground, a littlr biasing and a coupe of protection diodes across the finals just might work. I got spare parts and im retired so it'll be a winter project.

Bias voltage/circuit and input/output impedance match, will most certainly be different. I think it is easier to go from bipolar to MOSFET, than the other way around.

 

[vswr]

Perhaps you can find internal photos and compare them visually. The newer final is an equivalent of the IRFZ24, which seems to be robust and dirt cheap.

Cool to know. I'll look it up. But get this. I bought 2 10 packs of the rd16 type. Completely different sellers. 1 on ebay the other amazon. They were blowing my fuses. All tested good on my transistor/mosfet tester. Not 1 of them worked. It is a complete rip off true, but it has me wondering how they are soooo capable of faking the test gear....

 

[SuperLid]

Cool to know. I'll look it up. But get this. I bought 2 10 packs of the rd16 type. Completely different sellers. 1 on ebay the other amazon. They were blowing my fuses. All tested good on my transistor/mosfet tester. Not 1 of them worked. It is a complete rip off true, but it has me wondering how they are soooo capable of faking the test gear....

They re-mark transistors that are working as they were intended to. Just not in your application.

 

[vswr]

Finally got a good rd16hhf1 mosfet and it works great on AM but there is/was a 10 ohm surface mount micro resistor that fried when i switched over to ssb but only when I keyed the mic in ssb. The resistor continues to smoke even after unkeying and then if I switch to AM it stops fry mode. Switch Back to ssb, i can listen all day. The moment I key, fry mode begins. The mosfet is fine. Without a schematic its been a real pig to work on. Not even adding any mod. I replaced it with a regular 8th watt 10 ohm and it gets smokin hot the moment I key on ssb without mod. Trying to figure out what that resistor does. In transistor rigs, I'd assume its for biasing the final. Its very close to the mosfet also. When it burnt up the 1st time I lost my carrier so it has to have something to do with the final????? Anyone have any technical idea??