[ARC5] BC-230 first run

[AKLDGUY .]

Terry wrote:

> I'm rooting for yous. Bought one of those a few years back when
> Dave was experiment with using the 6C4's in it. Got a pair of
> coils for it but neither are dead on the 80 or 40mtrs.
> Have also got a couple big Philco console that have 6A3's
> in the audio output and was thinking these might be fun to play with.

Great to hear you got yours going (with 6C4's?). Let us know how
the 6A3's work out.

73 de Neil ZL1ANM




On 3/28/16, AKLDGUY . <neilb0627 at gmail.com> wrote:
> Glen Zook wrote:
>
>> I am not really familiar with the transmitter.  However, is it designed
>> to work into a 5-ohm load?  That is almost a dead short where r.f. is
>> concerned.
>>
>> You indicated a dummy load of 5-each 1-ohm resistors in series.
>> I would try 5-each 10-ohm resistors to get the load impedance up to
>> 50-ohms.
>
> An HF antenna on a plane is very short electrically. Consequently the
> impedance is about 5 ohms plus some capacitance. This is the
> impedance that the set and the ARC-5 transmitters are designed to
> work into. They will not properly work into a 50 ohm antenna unless
> some kind of impedance matcher is present.
> I appreciate you reading and commenting, though. Thanks.
>
> 73 de Neil ZL1ANM
>
>
> On 3/28/16, AKLDGUY . <neilb0627 at gmail.com> wrote:
>> Dave Stinson wrote:
>>
>>> Inspect the coil connection posts.  Hard to get to
>>> the backs of them but not impossible.  Make sure they connect
>>> where they should, especailly ground points.
>>
>> Do you mean the wiring may have been modified by a previous
>> owner (no, it hasn't been modified in any way) or that the
>> connections are prone to going O/C with old age?
>>
>>> Are the 6AQ5 screens connected to plate or grid?
>>> Must go to plate.
>>
>> They go to plate.
>>
>>> Jumper the RF Ammeter. Open thermocouple is
>>> another common problem.
>>
>> That's easily tryable. I'll check that out when I return after lunch.
>>
>>> If not any of these, I'll get my manuals and
>>> start scratching my head.
>>
>> Thanks. I wondered whether I had overlooked some setting.
>>
>> 73 de Neil ZL1ANM
>>
>>
>> On 3/28/16, AKLDGUY . <neilb0627 at gmail.com> wrote:
>>> Leslie wrote:
>>>
>>>> If the output tank circuit was "way off" resonance I'd expect more
>>>> current in the plate circuit.
>>>> My hunch is that there is a discrepancy between the resonant frequency
>>>> of the grid and plate tank circuits.
>>>> (But the grid cct is untuned.  Only the plate circuit is tuned.)
>>>>
>>>> I would suspect corrosion in the contacts somewhere - maybe the tank
>>>> "C".
>>>> I think that's C17.  Check the wiper on the rotor for C-17
>>>
>>> Yes, my instinct was that the final tank is way off tune, but in that
>>> case
>>> there should be more plate current and it should be 'dippable' to 25mA
>>> at resonance. I'll inspect the rotor wiper, but the capacitor looks
>>> pristine, so not hopeful.
>>>
>>>> If you make a "loop" with a neon on it, does the neon light?
>>>> If you make a "sniffer coil" with a 6V or 2V incandescent globe does it
>>>> light?
>>>
>>> The neon loop sounds like a good idea. I may pick up a neon at Jaycar
>>> while out for lunch today, if they're open this holiday weekend.
>>>
>>> 73 de Neil ZL1ANM
>>>
>>
>