[ARC5] Transistorized ARC-5 Receiver

[Spencer Petri]

Years ago I converted an LM freq meter to solid state using MPF102s,
except in the audio. It was a fairly easy conversion, the calibration
stayed intact. The paperwork is long gone and that's all I remember
about it except I ran it with a 9 V battery. de Pete WA5JCI

On 1/2/17, Phillip Carpenter <carpenterpa at tds.net> wrote:
> Reading and studying the Solid State Q5er article in detail shows that the
> author, Bob Grabowski, W5TKP, built two versions. The first was experimental
> and used first generation transistors such as 2N1639 for the mixer and 2N384
> for the oscillator. Also the originals coils were altered. It was a fair
> amount of work and destroyed the Command receivers original componentry.
>
> However, a second version did not alter any of the original coils or
> components. Also it used FETs, namely  seven TIS34s for all the stages
> except the detector which used two 2N1306s.
>
> Results were claimed to be excellent. This means we could make plug in FET
> substitution units using octal adapters (these are available on eBay from
> China sources for 2pcs for $10.49 shipped).
>
> I'm going to start with a plug in substitute for the 12K8 and see if
> performance is notably improved.
>
> Phillip W4RTX
>
> Sent from my iPhone
>
>> On Jan 2, 2017, at 12:33 PM, Glen Zook <gzook at yahoo.com> wrote:
>>
>> Plastic 2N4416 transistors, which are, basically, the same as the MPF-102,
>> are still available from Mouser.
>>
>>
>>
>> Leaded J-310 are also available from Mouser for $3.47 in single quantities
>> and for $2.79 each in quantities of 10.  The surface mount J-310 are
>> available for as little as $0.31 in single quantities and $0.201 (yes,
>> $0.201) each in quantities of 10 (make for total of $2.01 for 10) again
>> from Mouser.
>>
>>
>>
>> Glen, K9STH
>>
>> Website: http://k9sth.net
>>
>>
>> From: MICHAEL ST ANGELO <mstangelo at comcast.net>
>> To: Phillip Carpenter <carpenterpa at tds.net>; Brian
>> <brianclarke01 at optusnet.com.au>; Jim Haynes <jhhaynes at earthlink.net>
>> Cc: arc5 at mailman.qth.net
>> Sent: Monday, January 2, 2017 10:17 AM
>> Subject: Re: [ARC5] Transistorized ARC-5 Receiver
>>
>>  Brian,
>>
>> That's the path I took; replaced all circuitry except the frequency
>> determining components such as the capacitors, inductors and transformers.
>> If someone is concerned about upgrading a set with tubes there are lots of
>> carcasses around minus the tubes to resurrect.
>>
>> MPF-102's have been obsolete for years but J310 are still being produced
>> and is a better alternative. Unfortunately the production of leaded
>> thru-hole devices has been discontinued but SMT devices are available.
>>
>> I purchased leaded J310s from Arrow Electronics last year. I checked today
>> and they are on backorder.
>>
>> I also stocked up an leaded bipolar transistors such as the 2N3904 and
>> 2N3906 at that time.
>>
>> Dan's Small Parts still has leaded devices.
>>
>> With regards to plug-in replacements I would be more interested with solid
>> state replacements for some of the transmitting tubes which are hard to
>> find such as the 211E in the BC-375.
>>
>>
>