Frequently Asked Questions

Frequently Asked Questions

Frequently Asked Questions

Frequently Asked Questions

The descriptions below assume an understanding of the Elecraft® K2.
If you are unfamiliar with the K2, you may find it helpful to first visit
the K2 Internal Option Basics and Understanding Un-Modules pages.
Please refer to the site index page to lo­cate FAQs about our prod­ucts.

“Op­tion Ready” means that any in­ter­nal options can be in­stalled with­out re­quir­ing ma­jor dis­as­sem­bly of the en­clo­sure, and with­out re­quir­ing any ad­di­tion­al sol­der­ing on the K2’s three main cir­cuit boards.  How­ev­er pri­or to in­stal­la­tion, some op­tions will still re­quire that you first per­form ad­di­tion­al as­sem­bly steps as de­scribed in their man­u­als.  These steps can be quite in­volved for the op­tions that in­stall in the top cov­er.  In con­trast, there are just a few steps for the op­tions that mount on the K2’s main cir­cuit boards:

  • KAF2 or KDSP2 – Re­place a ma­chine screw se­cur­ing the Con­trol board, with the (op­tion pro­vid­ed) hex spac­er.
  • K60XV & K160RX – In­stall the ad­di­tion­al (op­tion sup­plied) con­nect­or(s) on the rear I/O pan­el.

Af­ter in­stal­la­tion, you must al­so per­form the pro­ce­dures list­ed be­low, per the op­tion’s man­u­al:

  • K160RX – Re­a­lign­ment of RF-L2 and L4, the 80/160 me­ter band­pass fil­ter in­duc­tors.
  • K60XV – 60 me­ter VCO check and the pos­si­ble need to ad­just RF-L30 and re­do VCO align­ment.
  • KSB2 – Beat Fre­quen­cy Os­cil­la­tor (BFO) and crys­tal fil­ter set­up.  It may al­so be nec­es­sary to re-jump­er the mic con­fig­u­ra­tion head­er be­hind the front pan­el.  This step can be avoid­ed if the head­er is pre-con­fig­ured for your mi­cro­phone dur­ing as­sem­bly.  That is, un­less you lat­er de­cide to use a mi­cro­phone with a dif­fer­ent con­nect­or pin-out, or one re­quir­ing a dif­fer­ent bi­as re­sis­tance.  The best way to avoid pos­si­bly hav­ing to dis­as­sem­ble the front sec­tion of your K2 to ac­com­mo­date a dif­fer­ent mi­cro­phone, is to also install our Internal Mic Adaptor (IMA) during the initial build.

Our re­work-free “Op­tion Ready” al­ter­nate as­sem­bly meth­od may not be ap­pro­pri­ate for eve­ry­one, par­tic­u­lar­ly build­ers who:

  • just feel more com­fort­a­ble ex­act­ly fol­low­ing the man­u­fac­tur­er’s as­sem­bly in­struc­tions.
  • wish to build the base ra­dio for the ab­so­lute min­i­mum (in­itial) cost.
  • do not plan to ev­er add any in­ter­nal op­tions.
  • find the an­no­tat­ed K2 man­u­al pag­es in our Com­pan­ion Guides too con­fus­ing or too much ad­di­tion­al work to fol­low.
  • have the nec­es­sary skills and equip­ment to per­form the PCB re­work that’s oth­er­wise nec­es­sary to add some op­tions.
  • do not mind sig­nif­i­cant­ly dis­as­sem­bling the en­clo­sure as re­quired to add most op­tions.
  • are not con­cerned about the re­sale val­ue of their ra­dio.
What is an “Option Ready” K2?
Option Ready K2 #5048

An “Option Ready” K2 is one that has been up­grad­ed to pre­pare it for the in­stal­la­tion of all pos­si­ble options.  As shown above, bypass headers are in­stalled in place of the six op­tions – KAF2, KDSP2, KNB2, KSB2, K60XV, & K160RX  – which mount di­rect­ly on the K2’s main cir­cuit boards.  These inexpensive devices re­store the as­so­ci­at­ed circuit connections which must be bro­ken to pre­pare the K2 to sup­port their as­so­ci­at­ed op­tion.  (No cor­re­spond­ing by­pass de­vices are re­quired for the op­tions that in­stall in the K2’s top cov­er.)

Go­ing one step fur­ther, the de­tailed in­struc­tions in our Companion Guides de­scribe how to seam­less­ly in­te­grate these “op­tion prep­a­ra­tion” up­grades dur­ing the in­itial as­sem­bly proc­ess.  Be­yond sim­pli­fy­ing the task of add­ing the op­tions, this ap­proach al­so elim­i­nates the need to per­form the PCB rework that’s oth­er­wise re­quired, pri­or in­stall­ing five of the six op­tions that mount di­rect­ly on the K2’s main cir­cuit boards.

What are the benefits of “Option Ready” assembly?

Re­work-free “Op­tion Ready” K2 con­struc­tion seam­less­ly com­bines in­itial as­sem­bly with all re­quired “in­ter­nal-op­tion-prep­a­ra­tion” chang­es.  This eliminates the need for the significant disassembly that’s oth­er­wise re­quired when add­ing most options.  Thus an “Op­tion Ready” K2 will be far eas­i­er to up­grade.  The time you’ll save add­ing the op­tions will more than make up for the ex­tra time ta­ken to build your K2 “Op­tion Ready” in the first place, so over­all you’ll have a more re­ward­ing kit build­ing ex­pe­ri­ence.

In ad­di­tion to avoid­ing the wear and tear from re­peat­ed­ly dis­as­sem­bling and re­as­sem­bling the en­clo­sure, you’ll al­so avoid the PCB re­work that’s nor­mal­ly re­quired when add­ing some op­tions.  Elim­i­nat­ing PCB re­work re­duc­es the pos­si­bil­i­ty of se­ri­ous­ly dam­ag­ing the K2’s cir­cuit boards, and can po­ten­tial­ly re­sult in a more re­li­a­ble ra­dio.

What’s normally required to add options?

Pri­or to in­stall­ing nine of the ten avail­a­ble in­ter­nal options, ad­di­tion­al op­tion sup­plied parts must first be add­ed to the K2, and a small num­ber of orig­i­nal parts must be re­moved.  This pack­ag­ing strat­e­gy – of pro­vid­ing some K2 parts with the op­tions that re­quire them in­stead of with the base ra­dio – is one of the rea­sons the “stock” K2 is such a bar­gain!

Pack­ag­ing the K2 this way does have its trade­offs:  (1) a small amount of PCB re­work is re­quired to re­place some orig­i­nal K2 parts; and (2) dis­as­sem­bly of the en­clo­sure is re­quired when add­ing most op­tions.  For sev­en op­tions this dis­as­sem­bly is ex­ten­sive, re­quir­ing re­mov­al of ei­ther the rear I/O pan­el heat­sink, the Con­trol cir­cuit board, or the Front Pan­el cir­cuit board. 

Ful­ly load­ing a new K2 with op­tions en­tails the in­stal­la­tion of 27 ad­di­tion­al parts, (15 com­po­nents and 12 con­nect­ors).  There are eight in­stanc­es where orig­i­nal K2 parts must be re­moved to per­mit the in­stal­la­tion of one or more of these op­tion-sup­plied parts (i.e. PCB re­work is re­quired).  The spe­cif­ics of this re­work are as fol­lows:

  • Re­sis­tor RF-R88 is changed from 470 Ω to 2.7 kΩ.
  • Re­sis­tor RF-R89 is re­placed with a jump­er wire.
  • Jump­er wire RF-W2 is re­placed by SIP mat­ing con­nect­or RF-J9.
  • Jump­er wire RF-W3 is re­placed by SIP mat­ing con­nect­or RF-J10.
  • Ze­ro-Ohm re­sis­tors (i.e. jump­er wires) CTRL-R18 & R19 are re­moved so that SIP mat­ing con­nect­ors CTRL-J1 & J2 can be in­stalled.
  • Ca­pac­i­tor RF-C6 is re­placed by SIP mat­ing con­nect­or RF-J15.
  • Ca­pac­i­tor RF-C71 is changed from 82 pF to 120 pF.

Sev­en oth­er orig­i­nal K2 parts must al­so be removed:

  • Resistor RF-R90.
  • Capacitor RF-C167.
  • Jumper wires RF-W1,W2,W3,W5,W6.

These chang­es – the re­mov­al of 13 orig­i­nal K2 parts and the in­stal­la­tion of 27 ad­di­tion­al parts – 9 on the Front Pan­el board, 2 on the Con­trol board, and 16 on the RF board – re­quire at least par­tial dis­as­sem­bly of the K2 en­clo­sure.  For sev­en options, ex­ten­sive dis­as­sem­bly of the en­clo­sure is re­quired to in­itial­ly pre­pare a “stock” K2 for their in­stal­la­tion.

How exactly do the two assembly methods differ?
close-up of UN-KNB2 header installed

The end re­sult of both as­sem­bly meth­ods is es­sen­tial­ly the same; at least it’s sup­posed to be!  How­ev­er, de­pend­ing up­on your de­sol­der­ing skills and your ac­cess to spe­cial­ized de­sol­der­ing equip­ment, the tra­di­tion­al as­sem­bly meth­od might leave your K2 with serious circuit board damage af­ter you’ve at­tempt­ed to add some of the options.

To elim­i­nate the pos­si­bil­i­ty of cir­cuit board dam­age while im­prov­ing re­li­a­bil­i­ty, our “Option Ready” meth­od has you build the ra­dio so that no de­sol­der­ing is re­quired when in­stall­ing the op­tions.  Un­til the op­tions are in­stalled, un-modules – ti­ny op­tion by­pass head­ers like the one shown above – take their place in­side the K2.

It is only af­ter the ra­dio is com­plet­ed and it’s time to add the op­tions, that the dif­fer­ence be­tween the two meth­ods tru­ly be­comes ap­par­ent.  The spe­cif­ic dif­fer­enc­es are shown in the ta­ble be­low, which com­pares the ad­di­tion­al steps re­quired to add all of the op­tions.  (The ta­ble doesn’t list all of the steps; just the ones that dif­fer.)

Tra­di­tion­al by the Book Stock K2 “Op­tion Ready” K2

Completely disassemble the enclosure:

  • Re­move the side pan­els.
  • Re­move the Con­trol board.
  • Re­move and dis­as­sem­ble the Front Pan­el.
  • Re­move the bot­tom cov­er and low­er-rear-pan­el/heat­sink.

Unsolder/remove 13 original parts:

  • Two jump­er wires from the bot­tom of the Con­trol board.
  • Five jump­ers, three re­sis­tors, and two caps – from the top of the RF board.
  • One cap from the bot­tom of the RF board.

Install/solder 27 additional parts:

  • Two SIP con­nect­ors on the top of the Con­trol board.
  • Five caps, one re­sis­tor, one re­sis­tor net­work, and one tran­sis­tor – on the top of the Front Pan­el board.
  • One DIP con­nect­or on the bot­tom of the Front Pan­el board.
  • Sev­en SIP con­nect­ors, four caps, two di­odes, two plugs, one re­sis­tor, and one jump­er wire – on the top of the RF board.

Install four standoffs on the RF board.

Reassemble the enclosure:

  • In­stall the bot­tom cov­er and low­er-rear-pan­el/heat­sink.
  • Re­as­sem­ble and in­stall the Front Pan­el.
  • In­stall the Con­trol board.
  • In­stall the side pan­els.
Un­plug the op­tion by­pass head­ers.

As you can see, it’s easy to add options to an “Option Ready” K2.  In con­trast, a con­sid­er­a­ble num­ber of ad­di­tion­al steps which could have been avoid­ed, are re­quired to “pre­pare” a K2 that has been as­sem­bled us­ing the tra­di­tion­al ap­proach.  But what isn’t im­me­di­ate­ly ob­vi­ous is that if you add the op­tions one at a time, then you must (at least par­tial­ly) dis­as­sem­ble and re­as­sem­ble the en­clo­sure many times over!

What additional parts are required?

Build­ing an “Option Ready” K2 re­quires …

  1. Option Bypass Headers.
  2. All of the unique K2 PCB parts that are pro­vid­ed with the K2 in­ter­nal options (In a few cas­es two dif­fer­ent Elecraft® op­tions pro­vide the same K2 parts.)

If you buy a ful­ly load­ed (QRP or QRO) K2 to start with, then you will al­ready have all of the nec­es­sary K2 PCB parts.  If you get some op­tions with your K2, then you’ll al­ready have some of the required parts.  If you are start­ing out with just a stock K2, then you’ll need all of the parts pro­vid­ed by our All Option Supplied Parts kit. 

If you are get­ting some op­tions with your in­itial K2 pur­chase, then please con­tin­ue read­ing below to de­ter­mine which of our in­di­vid­u­al parts kits you’ll need …

Which of your “parts kits” do I need?
K2 Parts Cross-Reference Table.

Build­ing an “Op­tion Ready” K2 re­quires 46 additional parts which are pro­vid­ed with Ele­craft’s op­tion­al K2 in­ter­nal ex­pan­sion mod­ules (options) So the an­swer de­pends on which op­tions you al­ready have.  The more op­tions you get up front be­fore you start build­ing your K2, the few­er ad­di­tion­al parts you’ll need to ob­tain from us.

Since there are 431 val­id op­tion con­fig­u­ra­tions, it isn’t prac­ti­cal to list eve­ry pos­si­ble com­bi­na­tion here.  For­tu­nate­ly, it is rel­a­tive­ly easy to de­ter­mine what’s re­quired for any com­bi­na­tion of Elecraft® op­tions.  Still, prop­er­ly an­swer­ing this ques­tion is suf­fi­cient­ly in­volved to war­rant de­vot­ing a sep­a­rate web­page to the sub­ject. 

The ta­ble on the What Else Do I Need? page match­es up our Duplicate K2 PCB Parts kits with the Elecraft® K2 op­tions that pro­vide the same parts.  Build­ing an “Option Ready” K2 re­quires the ad­di­tion­al parts list­ed in each row of that ta­ble, what­ev­er way you choose to ob­tain them.

Can I make my existing K2 “Option Ready”?

Yes you can, how­ev­er you may not want to for the K60XV un­less you will def­i­nite­ly be in­stall­ing it.  This is be­cause the Op­tion Ready prep­a­ra­tions for the K60XV will re­quire that you per­form some re­a­lign­ment of the K2 when the up­grade chang­es are made, and pos­si­bly a sec­ond time when the op­tion is ac­tu­al­ly in­stalled.

This con­cern does not ap­ply if you wait to make the chang­es un­til you are ready to in­stall the K60XV, since you’ll have to do this re­a­lign­ment then any­way.  It al­so does not ap­ply to build­ing an “Option Ready” K2 from the out­set.  It is only an is­sue for up­grad­ing an ex­ist­ing K2.  If you are al­ready in­tend­ing to do a top to bot­tom re­a­lign­ment any­way, then this con­cern is not ap­pli­ca­ble. 

An­oth­er pos­si­ble con­cern is that your firm­ware must at least be what has been ship­ping since S/N 4060.  Spe­cif­i­cal­ly, 2.04P or lat­er main MCU (U6, Con­trol board), and re­vi­sion 1.09 or lat­er I/O Con­trol­ler (U1, RF board).  This is nec­es­sary in or­der to en­a­ble the Ex­tend­ed VCO Range (D19) Sec­ond­ary Me­nu set­ting.

Please contact us if you have still have ques­tions about mak­ing your ex­ist­ing K2 “Op­tion Ready” for the K60XV op­tion.

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Updated 1301 UTC Sunday 11 MAY 2014
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