The results of a planet are relative to the strength and weakness of the entire birth chart. Bhaiyaji says ,it would be worthwhile in this context to look at some peculiarities of Rahu and Ketu.
VargottamaScientifically the Earth and the Moon move alone in defined paths in the heavens, creating different fields of forces in the process. These relative fields and the equilibrium between their forces are disturbed when the paths of the Earth and the Moon intersect. Rahu and Ketu are two points representing the cross roads in the fields of force of the Earth and Sun and  Moon and are two points of disturbance. At the time of an eclipse, the radiation and electromagnetic vibrations coming from the Moon or the Sun are cut off and normal conditions that obtain for the Earth get disturbed.
Those born during eclipses, due to this disturbance, have been found to suffer mildly and sometimes seriously from mental abnormality and even physical conditions.
The planetary influences get modified when they come in contact with Rahu and Ketu.WheneverRahu is in conjunction with a planet, it enhances its influence and basic quality towards bhoga (enjoyment) and sangraha (accumulation) while Ketu relieves the planet of its basic quality.Ketu is also said to increase the intellectual properties of the planet greatly if the horoscope so permits.
Further by absorbing the results of the conjunct planet both Rahu and Ketu afflict it and make it weak.They also afflict the Sun and the Moon and are taken to have comparatively stronger influence as compared to other planets.
While considering the influence of Rahu and Ketu, one must consider their dispositions which are called Karmic Control Planets. It is said that since Ketu is the inlet point of Karma, the planet ruling the sign occupied by Ketu is said to show incoming or past life Karmic control while the planet ruling the sign occupied by Rahu controls Karmic distribution in this life.
The Karmic Control Planets have strong implications depending upon where they are placed in birth chart and the aspect ( drishti) , they have with the Nodal axis.
While Rahu is said to be Arishta Nashaka (destroyer of adversity) in the 3rd, 6th, and 11th, before doing so, he would create Arishta Janya (adverse situation) which will then be resolved. In the 8th and 12th, Rahu or Ketu alone would be ordinarily unfavorable.
Dr. B.V. Raman in Hindu Predictive Astrology has given the Bhava and Rashi results for Rahu and Ketu. Reference may also be made to Chamatkara Chintamani for detailed results of the Nodes in different situations.
Understanding Nodal Nuances
The next point to be considered for the results of the Nodes in various houses and Rashis is with reference to their Yoga Karakattwa.
Bhaiyaji says according to Laghu Parasari, Sloka 13, strong Rahu and Ketu give the results of (a) the Bhava occupied by them; and (b) the Bhavas ruled by planet(s) conjunct with them. If Rahu or Ketu or both are in favorable houses, they would give favorable results. If in unfavorable houses, they would give bad results.
Rahu and Ketu, even if alone in Trikonas including the Ascendant, are favorable. They are neutral in 4th, 7th, and 10th. In the 3rd, 6th, and 11th, while Rahu is said to be Arisht Nashak (destroyer of adversity), but before doing so he would create Arishta Janya (adverse situation) which will then be resolved. In the 8th and 12th, Rahu or Ketu alone would be ordinarily unfavorable.
If Rahu or Ketu is conjunct another planet in a Trikona (1st, 5th, or 9th), Kendra (1st, 4th, 7th or the 10th), Trishadaya (3rd, 6th or the 11th), in the 8th or 2nd and 12th houses, the results as shown in Table I may be expected.
Rahu or Ketu in In Conjunction with Results
Kendra or quadrant Trinal lord (including Ascendant lord) Yogakaraka
Kendra lord of 3rd, 6th or 11th Unfavorable
Kendra 8th lord Unfavorable
Kendra 2nd or 12th lord Qualified by the other house owned by the 2nd or 12th lord
Kendra Benefic Kendra lord Unfavorable due to Kendradhipati Dosha
Kendra Malefic Kendra lord Neutral
7th House With Maraka Maraka Unfavorable
Trikona or Trine Kendra lord (including Ascendant lord) Yogakaraka
Trikona Trikona lord Favorable
Trikona 2nd or 12th lord Favorable
Trikona 3rd, 6th or 11th lord Favorable
Trikona 8th lord Favorable
3rd, 6th, or 11th Trinal lord Mixed Results
3rd, 6th or 11th Kendra lord Unfavorable
3rd, 6th or 11th 3rd, 6th or 11th lord Highly adverse
3rd, 6th or 11th 8th lord Adverse
3rd, 6th or 11th 2nd or 12th lord Unfavorable
8th Trinal lord Mixed Results
8th Kendra lord Unfavorable
8th 3rd, 6th or 11th Highly adverse
8th 8th lord Adverse
8th 2nd or 12th lord Unfavorable
8th 7th lord Maraka
2nd or 12th 7th lord Maraka
2nd or 12th Karaka Favorable
2nd or 12th Benefic Kendra lord Unfavorable
2nd or 12th Malefic Kendra lord Neutral
2nd or 12th 3rd, 6th or 11th lord Unfavorable
2nd or 12th 8th lord Unfavorable
2nd or 12th 2nd or 12th lord Favorable according to the nature of the 2nd or 12th lord
If Rahu and Ketu are placed as in Table I and in malefic signs in Rasi or Navamsa or in the 2nd, 12th, 3rd, 6th or 8th they tend to increasingly reduce happiness from the relatives indicated by the Bhava occupied by them. This may be due to quarrels and strained relations, by living at a great distance from relatives or their untimely demise. However, Rahu may produce material prosperity resulting from the signification or Karakattwa of the house in strange ways.
Detailed results of Rahu Dasa are given in Sarwartha Chintamani, Chapter 15, as translated with notes by Prof. B. Suryanarain Rao. Bhaiyaji tells us , about the following general results :-
(a) Rahu in Cancer, Taurus or Aries will give money, education and pleasure and recognition from the rulers, pleasure from wife, servants and happiness.
(b) Rahu in Virgo, Pisces and Sagittarius will give children, wife, lordship over the country, conveyances and in the end, loss of everything.
(c) Rahu in a malefic sign will cause leanness of body, destruction of relatives, fear from kings, deception by thieves, venereal complaints, asthma, consumption and urinal troubles.
(d) Rahu aspected by a malefic will cause irreligiousness , loss of service, sickness and troubles from thieves, cheating and fires.
(e) Rahu aspected by a benefic shows wealth from kings and death to relatives.
(f) Rahu with an exalted planet will lead to gain of kingdom, wife, children and wealth, clothes, ornaments, sweet scents.
(g) Rahu with debilitated planets will indicate livelihood by despicable means, bad food, bad spouse and worthless children.
(h) Rahu at the commencement of his Dasha gives sorrow, in the middle, reputation and happiness and in the end, change of place, loss of Guru, parents etc. These results would increase qualitatively when Rahu is Vargottama. The native would excel others in his field of activity. The area of activity would depend upon on Rahu’s Rasi, Navamsa and Nakshatra dispositors and the planets which are conjunct or aspected by Rahu.
As per Devakeralam, Vol. Ill, Verses 4850 – 4852 :-
(a) Should Rahu be in the 2nd (Scorpio) in Vargottama Navamsa, the subject will be given to enjoy pleasures. He will incur diseases in childhood. In the middle of his life, he will enjoy a great deal of prosperity. Old age will place him in debt and he will, to some extent, steal others’ wealth. He will be attached to his race, be famous among his family members and will suffer from physical illnesses. He will be honored by the king of kings, be revered by scholars and will earn fame.
(b) If Rahu in the 2nd is not Vargottama, the native’s son will be in the grip of debts.
(c) Rahu conjunct a benefic (in Scorpio) will lead t