8 watts form an HTX-202 is too much anyway, 5 watts off the battery,6 on
external power was normal, but the real early ones weren't good with
cooling, the later ones as long as you ran them in spec you were fine.
----- Original Message -----
From: "colin McDonald" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, March 19, 2011 9:54 PM
Subject: Re: Ht burning out?
> don't get long winded and everything will be just fine.
> also, the two units that were mentioned are very old radios...not sure if
> the article was written a long long time ago when these radios were new,
> or
> if this author just chooses to use boat anchor HT's...either way, I
> wouldn't
> worry too much about it, unless your going to be talking for long long
> periods of time and over an extended period.
> most modern HT's have a bigger heat sink and obviously better transistors
> than older stuff did.
> while the 202 might have been a good radio for it's time, it was a shadow
> compared to modern HT's...same holds true for the th22a.
>
> If this guy blew a final section in a year, he must have been yapping like
> an old fart on 75 meters or something.
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "KK4AHX Darren Duff" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Saturday, March 19, 2011 7:03 PM
> Subject: Ht burning out?
>
>
>> Hi.
>> After reading the below paragraph in an online article I am worried about
>> burning out my ht. It's the only rig I have now. I want to get a mobile
>> to
>> use as a base station but it's not in the budget right now. I would like
>> to
>> know what other's think. here is the snip from the article.
>>
>> HAND HELD DUTY CYCLE LIMITS
>>
>> If you subject today's HTs to frequent full power, 5w transmissions of
>> several minutes duration they overheat and the final power transistors
>> may
>> fail prematurely. Kenwood and Yaesu state in their service manuals that
>> their HTs are rated for 20% duty cycle at their maximum RF output, or 30
>> seconds of transmit to 2 minutes of standby. After I first got my
>> license,
>> I burned up three sets of "finals" in less than a year with long winded
>> QSOs using a Radio Shack HTX-202 which produced 8w when powered at 13.8V
>> from my auto cigarette lighter plug! When the warranty ran out, I
>> replaced
>> it with a Kenwood TH-22 and repeated the same result. Kenwood's Virginia
>> Beach service center politely admonished me that I was "exceeding the
>> recommended duty cycle" and should buy a mobile. I followed their advice
>> and am satisfied with my two Kenwood mobiles, but I sought out other HTs
>> and pass that advice along.
>>
>> Thanks, 73's.
>>
>> Darren Duff.
>>
>> amateur radio station KK4AHX.
>>
>>
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